From 279bf63e77a46e9ea31291af73f38cc0a667bc1f Mon Sep 17 00:00:00 2001
From: Daniel Freedman <dfreedm@google.com>
Date: Tue, 27 Oct 2015 11:32:55 -0700
Subject: [PATCH] Add `Polymer.dom.deepContains`

- Also add tests
---
 src/lib/dom-api.html                | 1942 ++++++++++++++-------------
 test/unit/polymer-dom-elements.html |   21 +-
 test/unit/polymer-dom-shadow.html   |    2 +
 test/unit/polymer-dom.html          |    2 +
 test/unit/polymer-dom.js            |   19 +-
 5 files changed, 1022 insertions(+), 964 deletions(-)

diff --git a/src/lib/dom-api.html b/src/lib/dom-api.html
index ebde2403b4..df38fc68f5 100644
--- a/src/lib/dom-api.html
+++ b/src/lib/dom-api.html
@@ -1,961 +1,981 @@
-<!--
-@license
-Copyright (c) 2014 The Polymer Project Authors. All rights reserved.
-This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
-The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
-The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
-Code distributed by Google as part of the polymer project is also
-subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
--->
-<link rel="import" href="settings.html">
-<link rel="import" href="dom-innerHTML.html">
-<script>
-
-  /**
-   * DomApi is a dom manipulation library which is compatible with both 
-   * Shady DOM and Shadow DOM. The general usage is 
-   * `Polymer.dom(node).method(arguments)` where methods and arguments
-   * match native DOM where possible.
-   */
-  Polymer.DomApi = (function() {
-    'use strict';
-
-    var Settings = Polymer.Settings;
-    var getInnerHTML = Polymer.domInnerHTML.getInnerHTML;
-
-    var nativeInsertBefore = Element.prototype.insertBefore;
-    var nativeRemoveChild = Element.prototype.removeChild;
-    var nativeAppendChild = Element.prototype.appendChild;
-    var nativeCloneNode = Element.prototype.cloneNode;
-    var nativeImportNode = Document.prototype.importNode;
-
-    var DomApi = function(node) {
-      this.node = node;
-      if (this.patch) {
-        this.patch();
-      }
-    };
-
-    // ensure nodes are wrapped if SD polyfill is present
-    if (window.wrap && Settings.useShadow && !Settings.useNativeShadow) {
-      DomApi = function(node) {
-        this.node = wrap(node);
-        if (this.patch) {
-          this.patch();
-        }
-      };
-    }
-
-    DomApi.prototype = {
-
-      flush: function() {
-        Polymer.dom.flush();
-      },
-
-      _lazyDistribute: function(host) {
-        // note: only try to distribute if the root is not clean; this ensures
-        // we don't distribute before initial distribution
-        if (host.shadyRoot && host.shadyRoot._distributionClean) {
-          host.shadyRoot._distributionClean = false;
-          Polymer.dom.addDebouncer(host.debounce('_distribute', 
-            host._distributeContent));
-        }
-      },
-
-      appendChild: function(node) {
-        return this._addNode(node);
-      },
-
-      insertBefore: function(node, ref_node) {
-        return this._addNode(node, ref_node);
-      },
-
-      // cases in which we may not be able to just do standard native call
-      // 1. container has a shadyRoot (needsDistribution IFF the shadyRoot
-      // has an insertion point)
-      // 2. container is a shadyRoot (don't distribute, instead set
-      // container to container.host.
-      // 3. node is <content> (host of container needs distribution)
-      _addNode: function(node, ref_node) {
-        this._removeNodeFromParent(node);
-        var addedInsertionPoint;
-        var root = this.getOwnerRoot();
-        // if a <content> is added, make sure it's parent has logical info.
-        if (root) {
-          addedInsertionPoint = this._maybeAddInsertionPoint(node, this.node);
-        }
-        if (this._nodeHasLogicalChildren(this.node)) {
-          if (ref_node) {
-            var children = this.childNodes;
-            var index = children.indexOf(ref_node);
-            if (index < 0) {
-              throw Error('The ref_node to be inserted before is not a child ' +
-                'of this node');
-            }
-          }
-          this._addLogicalInfo(node, this.node, index);
-        }
-        this._addNodeToHost(node);
-        // if not distributing and not adding to host, do a fast path addition
-        if (!this._maybeDistribute(node, this.node) && 
-          !this._tryRemoveUndistributedNode(node)) {
-          if (ref_node) {
-            // if ref_node is <content> replace with first distributed node
-            ref_node = ref_node.localName === CONTENT ?
-              this._firstComposedNode(ref_node) : ref_node;
-          }
-          // if adding to a shadyRoot, add to host instead
-          var container = this.node._isShadyRoot ? this.node.host : this.node;
-          addToComposedParent(container, node, ref_node);
-          if (ref_node) {
-            nativeInsertBefore.call(container, node, ref_node);
-          } else {
-            nativeAppendChild.call(container, node);
-          }
-        }
-        if (addedInsertionPoint) {
-          this._updateInsertionPoints(root.host);
-        }
-        this.notifyObserver();
-        return node;
-      },
-
-      /**
-        Removes the given `node` from the element's `lightChildren`.
-        This method also performs dom composition.
-      */
-      removeChild: function(node) {
-        if (factory(node).parentNode !== this.node) {
-          console.warn('The node to be removed is not a child of this node',
-            node);
-        }
-        this._removeNodeFromHost(node);
-        if (!this._maybeDistribute(node, this.node)) {
-          // if removing from a shadyRoot, remove form host instead
-          var container = this.node._isShadyRoot ? this.node.host : this.node;
-          // not guaranteed to physically be in container; e.g.
-          // undistributed nodes.
-          if (container === node.parentNode) {
-            removeFromComposedParent(container, node);
-            nativeRemoveChild.call(container, node);
-          }
-        }
-        this.notifyObserver();
-        return node;
-      },
-
-      replaceChild: function(node, ref_node) {
-        this.insertBefore(node, ref_node);
-        this.removeChild(ref_node);
-        return node;
-      },
-
-      _hasCachedOwnerRoot: function(node) {
-        return Boolean(node._ownerShadyRoot !== undefined);
-      },
-
-      getOwnerRoot: function() {
-        return this._ownerShadyRootForNode(this.node);
-      },
-
-      _ownerShadyRootForNode: function(node) {
-        if (!node) {
-          return;
-        }
-        if (node._ownerShadyRoot === undefined) {
-          var root;
-          if (node._isShadyRoot) {
-            root = node;
-          } else {
-            var parent = Polymer.dom(node).parentNode;
-            if (parent) {
-              root = parent._isShadyRoot ? parent :
-                this._ownerShadyRootForNode(parent);
-            } else {
-             root = null;
-            }
-          }
-          node._ownerShadyRoot = root;
-        }
-        return node._ownerShadyRoot;
-      },
-
-      _maybeDistribute: function(node, parent) {
-        // TODO(sorvell): technically we should check non-fragment nodes for
-        // <content> children but since this case is assumed to be exceedingly
-        // rare, we avoid the cost and will address with some specific api
-        // when the need arises.  For now, the user must call
-        // distributeContent(true), which updates insertion points manually
-        // and forces distribution.
-        var fragContent = (node.nodeType === Node.DOCUMENT_FRAGMENT_NODE) &&
-          !node.__noContent && Polymer.dom(node).querySelector(CONTENT);
-        var wrappedContent = fragContent &&
-          (Polymer.dom(fragContent).parentNode.nodeType !==
-          Node.DOCUMENT_FRAGMENT_NODE);
-        var hasContent = fragContent || (node.localName === CONTENT);
-        // There are 2 possible cases where a distribution may need to occur:
-        // 1. <content> being inserted (the host of the shady root where
-        //    content is inserted needs distribution)
-        // 2. children being inserted into parent with a shady root (parent
-        //    needs distribution)
-        if (hasContent) {
-          var root = this._ownerShadyRootForNode(parent);
-          if (root) {
-            var host = root.host;
-            // note, insertion point list update is handled after node 
-            // mutations are complete
-            this._lazyDistribute(host);
-          }
-        }
-        var parentNeedsDist = this._parentNeedsDistribution(parent);
-        if (parentNeedsDist) {
-          this._lazyDistribute(parent);
-        }
-        // Return true when distribution will fully handle the composition
-        // Note that if a content was being inserted that was wrapped by a node,
-        // and the parent does not need distribution, return false to allow
-        // the nodes to be added directly, after which children may be
-        // distributed and composed into the wrapping node(s)
-        return parentNeedsDist || (hasContent && !wrappedContent);
-      },
-
-      /* note: parent argument is required since node may have an out
-      of date parent at this point; returns true if a <content> is being added */
-      _maybeAddInsertionPoint: function(node, parent) {
-        var added;
-        if (node.nodeType === Node.DOCUMENT_FRAGMENT_NODE && 
-          !node.__noContent) {
-          var c$ = factory(node).querySelectorAll(CONTENT);
-          for (var i=0, n, np, na; (i<c$.length) && (n=c$[i]); i++) {
-            np = factory(n).parentNode;
-            // don't allow node's parent to be fragment itself
-            if (np === node) {
-              np = parent;
-            }
-            na = this._maybeAddInsertionPoint(n, np);
-            added = added || na;
-          }
-        } else if (node.localName === CONTENT) {
-          saveLightChildrenIfNeeded(parent);
-          saveLightChildrenIfNeeded(node);
-          added = true;
-        }
-        return added;
-      },
-
-      _tryRemoveUndistributedNode: function(node) {
-        if (this.node.shadyRoot) {
-          var parent = getComposedParent(node);
-          if (parent) {
-            nativeRemoveChild.call(parent, node);
-          }
-          return true;
-        }
-      },
-
-      _updateInsertionPoints: function(host) {
-        var i$ = host.shadyRoot._insertionPoints =
-          factory(host.shadyRoot).querySelectorAll(CONTENT);
-        // ensure <content>'s and their parents have logical dom info.
-        for (var i=0, c; i < i$.length; i++) {
-          c = i$[i];
-          saveLightChildrenIfNeeded(c);
-          saveLightChildrenIfNeeded(factory(c).parentNode);
-        }
-      },
-
-      // a node has logical children
-      _nodeHasLogicalChildren: function(node) {
-        return Boolean(node._lightChildren !== undefined);
-      },
-
-      _parentNeedsDistribution: function(parent) {
-        return parent && parent.shadyRoot && hasInsertionPoint(parent.shadyRoot);
-      },
-
-      _removeNodeFromParent: function(node) {
-        // note: we may need to notify and not have logical info so fallback
-        // to composed parentNode.
-        var parent = node._lightParent || node.parentNode;
-        if (parent && hasDomApi(parent)) {
-          factory(parent).notifyObserver();
-        }
-        this._removeNodeFromHost(node, true);
-      },
-
-      // NOTE: if `ensureComposedRemoval` is true then the node should be
-      // removed from its composed parent.
-      _removeNodeFromHost: function(node, ensureComposedRemoval) {
-        // note that it's possible for both the node's host and its parent 
-        // to require distribution... both cases are handled here.
-        var hostNeedsDist;
-        var root;
-        var parent = node._lightParent;
-        if (parent) {
-          // distribute node's parent iff needed
-          factory(node)._distributeParent();
-          root = this._ownerShadyRootForNode(node);
-          // remove node from root and distribute it iff needed
-          if (root) {
-            root.host._elementRemove(node);
-            hostNeedsDist = this._removeDistributedChildren(root, node);
-          }
-          this._removeLogicalInfo(node, parent);
-        }
-        this._removeOwnerShadyRoot(node);
-        if (root && hostNeedsDist) {
-          this._updateInsertionPoints(root.host);
-          this._lazyDistribute(root.host);
-        } else if (ensureComposedRemoval) {
-          removeFromComposedParent(getComposedParent(node), node);
-        }
-      },
-
-      _removeDistributedChildren: function(root, container) {
-        var hostNeedsDist;
-        var ip$ = root._insertionPoints;
-        for (var i=0; i<ip$.length; i++) {
-          var content = ip$[i];
-          if (this._contains(container, content)) {
-            var dc$ = factory(content).getDistributedNodes();
-            for (var j=0; j<dc$.length; j++) {
-              hostNeedsDist = true;
-              var node = dc$[j];
-              var parent = node.parentNode;
-              if (parent) {
-                removeFromComposedParent(parent, node);
-                nativeRemoveChild.call(parent, node);
-              }
-            }
-          }
-        }
-        return hostNeedsDist;
-      },
-
-      _contains: function(container, node) {
-        while (node) {
-          if (node == container) {
-            return true;
-          }
-          node = factory(node).parentNode;
-        }
-      },
-
-      // a node being added is always in this same host as this.node.
-      _addNodeToHost: function(node) {
-        var root = this.getOwnerRoot();
-        if (root) {
-          root.host._elementAdd(node);
-        }
-      },
-
-      _addLogicalInfo: function(node, container, index) {
-        var children = factory(container).childNodes;
-        index = index === undefined ? children.length : index;
-        // handle document fragments
-        if (node.nodeType === Node.DOCUMENT_FRAGMENT_NODE) {
-          // NOTE: the act of setting this info can affect patched nodes
-          // getters; therefore capture childNodes before patching.
-          var c$ = Array.prototype.slice.call(node.childNodes);
-          for (var i=0, n; (i<c$.length) && (n=c$[i]); i++) {
-            children.splice(index++, 0, n);
-            n._lightParent = container;
-          }
-        } else {
-          children.splice(index, 0, node);
-          node._lightParent = container;
-        }
-      },
-
-      // NOTE: in general, we expect contents of the lists here to be small-ish
-      // and therefore indexOf to be nbd. Other optimizations can be made
-      // for larger lists (linked list)
-      _removeLogicalInfo: function(node, container) {
-        var children = factory(container).childNodes;
-        var index = children.indexOf(node);
-        if ((index < 0) || (container !== node._lightParent)) {
-          throw Error('The node to be removed is not a child of this node');
-        }
-        children.splice(index, 1);
-        node._lightParent = null;
-      },
-
-      _removeOwnerShadyRoot: function(node) {
-        // optimization: only reset the tree if node is actually in a root
-        if (this._hasCachedOwnerRoot(node)) {
-          var c$ = factory(node).childNodes;
-          for (var i=0, l=c$.length, n; (i<l) && (n=c$[i]); i++) {
-            this._removeOwnerShadyRoot(n);
-          }
-        }
-        node._ownerShadyRoot = undefined;
-      },
-
-      // TODO(sorvell): This will fail if distribution that affects this
-      // question is pending; this is expected to be exceedingly rare, but if
-      // the issue comes up, we can force a flush in this case.
-      _firstComposedNode: function(content) {
-        var n$ = factory(content).getDistributedNodes();
-        for (var i=0, l=n$.length, n, p$; (i<l) && (n=n$[i]); i++) {
-          p$ = factory(n).getDestinationInsertionPoints();
-          // means that we're composed to this spot.
-          if (p$[p$.length-1] === content) {
-            return n;
-          }
-        }
-      },
-
-      // TODO(sorvell): consider doing native QSA and filtering results.
-      querySelector: function(selector) {
-        return this.querySelectorAll(selector)[0];
-      },
-
-      querySelectorAll: function(selector) {
-        return this._query(function(n) {
-          return matchesSelector.call(n, selector);
-        }, this.node);
-      },
-
-      _query: function(matcher, node) {
-        node = node || this.node;
-        var list = [];
-        this._queryElements(factory(node).childNodes, matcher, list);
-        return list;
-      },
-
-      _queryElements: function(elements, matcher, list) {
-        for (var i=0, l=elements.length, c; (i<l) && (c=elements[i]); i++) {
-          if (c.nodeType === Node.ELEMENT_NODE) {
-            this._queryElement(c, matcher, list);
-          }
-        }
-      },
-
-      _queryElement: function(node, matcher, list) {
-        if (matcher(node)) {
-          list.push(node);
-        }
-        this._queryElements(factory(node).childNodes, matcher, list);
-      },
-
-      getDestinationInsertionPoints: function() {
-        return this.node._destinationInsertionPoints || [];
-      },
-
-      getDistributedNodes: function() {
-        return this.node._distributedNodes || [];
-      },
-
-      /*
-        Returns a list of nodes distributed within this element. These can be
-        dom children or elements distributed to children that are insertion
-        points.
-      */
-      queryDistributedElements: function(selector) {
-        var c$ = this.getEffectiveChildNodes();
-        var list = [];
-        for (var i=0, l=c$.length, c; (i<l) && (c=c$[i]); i++) {
-          if ((c.nodeType === Node.ELEMENT_NODE) && 
-              matchesSelector.call(c, selector)) {
-            list.push(c);
-          }
-        }
-        return list;
-      },
-
-      /*
-        Returns a list of effective childNoes within this element. These can be
-        dom child nodes or elements distributed to children that are insertion
-        points.
-      */
-      getEffectiveChildNodes: function() {
-        var list = [];
-        var c$ = this.childNodes;
-        for (var i=0, l=c$.length, c; (i<l) && (c=c$[i]); i++) {
-          if (c.localName === CONTENT) {
-            var d$ = factory(c).getDistributedNodes();
-            for (var j=0; j < d$.length; j++) {
-              list.push(d$[j]);
-            }
-          } else {
-            list.push(c);
-          }
-        }
-        return list;
-      },
-
-      _clear: function() {
-        while (this.childNodes.length) {
-          this.removeChild(this.childNodes[0]);
-        }
-      },
-
-      setAttribute: function(name, value) {
-        this.node.setAttribute(name, value);
-        this._distributeParent();
-      },
-
-      removeAttribute: function(name) {
-        this.node.removeAttribute(name);
-        this._distributeParent();
-      },
-
-      _distributeParent: function() {
-        if (this._parentNeedsDistribution(this.parentNode)) {
-          this._lazyDistribute(this.parentNode);
-        }
-      },
-
-      cloneNode: function(deep) {
-        var n = nativeCloneNode.call(this.node, false);
-        if (deep) {
-          var c$ = this.childNodes;
-          var d = factory(n);
-          for (var i=0, nc; i < c$.length; i++) {
-            nc = factory(c$[i]).cloneNode(true);
-            d.appendChild(nc);
-          }
-        }
-        return n;
-      },
-
-      importNode: function(externalNode, deep) {
-        // for convenience use this node's ownerDoc if the node isn't a document
-        var doc = this.node instanceof Document ? this.node :
-          this.node.ownerDocument;
-        var n = nativeImportNode.call(doc, externalNode, false);
-        if (deep) {
-          var c$ = factory(externalNode).childNodes;
-          var d = factory(n);
-          for (var i=0, nc; i < c$.length; i++) {
-            nc = factory(doc).importNode(c$[i], true);
-            d.appendChild(nc);
-          }
-        }
-        return n;
-      },
-
-      /**
-       * Notifies callers about changes to the element's effective child nodes, 
-       * the same list as returned by `getEffectiveChildNodes`. 
-       * @param {function} callback The supplied callback is called with an 
-       * `info` argument which is an object that provides 
-       * the `target` on which the changes occurred, a list of any nodes 
-       * added in the `addedNodes` array, and nodes removed in the 
-       * `removedNodes` array.
-       * @return {object} Returns a handle which is the argument to 
-       * `unobserveNodes`.
-       */
-      observeNodes: function(callback) {
-        if (callback) {
-          if (!this.observer) {
-            this.observer = this.node.localName === CONTENT ?
-              new DomApi.DistributedNodesObserver(this) :
-              new DomApi.EffectiveNodesObserver(this);
-          }
-          return this.observer.addListener(callback);
-        }
-      },
-
-      /**
-       * Stops observing changes to the element's effective child nodes.
-       * @param {object} handle The handle for the callback that should
-       * no longer receive notifications. This handle is returned from 
-       * `observeNodes`.
-       */
-      unobserveNodes: function(handle) {
-        if (this.observer) {
-          this.observer.removeListener(handle);
-        }
-      },
-
-      notifyObserver: function() {
-        if (this.observer) {
-          this.observer.notify();
-        }
-      }
-
-    };
-
-    // changes and accessors...
-    if (!Settings.useShadow) {
-
-      Object.defineProperties(DomApi.prototype, {
-
-        childNodes: {
-          get: function() {
-            var c$ = getLightChildren(this.node);
-            return Array.isArray(c$) ? c$ : Array.prototype.slice.call(c$);
-          },
-          configurable: true
-        },
-
-        children: {
-          get: function() {
-            return Array.prototype.filter.call(this.childNodes, function(n) {
-              return (n.nodeType === Node.ELEMENT_NODE);
-            });
-          },
-          configurable: true
-        },
-
-        parentNode: {
-          get: function() {
-            return this.node._lightParent ||
-              getComposedParent(this.node);
-          },
-          configurable: true
-        },
-
-        firstChild: {
-          get: function() {
-            return this.childNodes[0];
-          },
-          configurable: true
-        },
-
-        lastChild: {
-          get: function() {
-            var c$ = this.childNodes;
-            return c$[c$.length-1];
-          },
-          configurable: true
-        },
-
-        nextSibling: {
-          get: function() {
-            var c$ = this.parentNode && factory(this.parentNode).childNodes;
-            if (c$) {
-              return c$[Array.prototype.indexOf.call(c$, this.node) + 1];
-            }
-          },
-          configurable: true
-        },
-
-        previousSibling: {
-          get: function() {
-            var c$ = this.parentNode && factory(this.parentNode).childNodes;
-            if (c$) {
-              return c$[Array.prototype.indexOf.call(c$, this.node) - 1];
-            }
-          },
-          configurable: true
-        },
-
-        firstElementChild: {
-          get: function() {
-            return this.children[0];
-          },
-          configurable: true
-        },
-
-        lastElementChild: {
-          get: function() {
-            var c$ = this.children;
-            return c$[c$.length-1];
-          },
-          configurable: true
-        },
-
-        nextElementSibling: {
-          get: function() {
-            var c$ = this.parentNode && factory(this.parentNode).children;
-            if (c$) {
-              return c$[Array.prototype.indexOf.call(c$, this.node) + 1];
-            }
-          },
-          configurable: true
-        },
-
-        previousElementSibling: {
-          get: function() {
-            var c$ = this.parentNode && factory(this.parentNode).children;
-            if (c$) {
-              return c$[Array.prototype.indexOf.call(c$, this.node) - 1];
-            }
-          },
-          configurable: true
-        },
-
-        // textContent / innerHTML
-        textContent: {
-          get: function() {
-            var nt = this.node.nodeType;
-            if (nt === Node.TEXT_NODE || nt === Node.COMMENT_NODE) {
-              return this.node.textContent;
-            } else {
-              var tc = [];
-              for (var i = 0, cn = this.childNodes, c; c = cn[i]; i++) {
-                if (c.nodeType !== Node.COMMENT_NODE) {
-                  tc.push(c.textContent);
-                }
-              }
-              return tc.join('');
-            }
-          },
-          set: function(text) {
-            var nt = this.node.nodeType;
-            if (nt === Node.TEXT_NODE || nt === Node.COMMENT_NODE) {
-              this.node.textContent = text;
-            } else {
-              this._clear();
-              if (text) {
-                this.appendChild(document.createTextNode(text));
-              }
-            }
-          },
-          configurable: true
-        },
-
-        innerHTML: {
-          get: function() {
-            var nt = this.node.nodeType;
-            if (nt === Node.TEXT_NODE || nt === Node.COMMENT_NODE) {
-              return null;
-            } else {
-              return getInnerHTML(this.node);
-            }
-          },
-          set: function(text) {
-            var nt = this.node.nodeType;
-            if (nt !== Node.TEXT_NODE || nt !== Node.COMMENT_NODE) {
-              this._clear();
-              var d = document.createElement('div');
-              d.innerHTML = text;
-              var c$ = Array.prototype.slice.call(d.childNodes);
-              for (var i=0; i < c$.length; i++) {
-                this.appendChild(c$[i]);
-              }
-            }
-          },
-          configurable: true
-        }
-
-      });
-
-      DomApi.prototype._getComposedInnerHTML = function() {
-        return getInnerHTML(this.node, true);
-      };
-
-
-    } else {
-
-      var forwardMethods = ['cloneNode', 'appendChild', 'insertBefore', 
-      'removeChild', 'replaceChild'];
-
-      forwardMethods.forEach(function(name) {
-        DomApi.prototype[name] = function() {
-          return this.node[name].apply(this.node, arguments);
-        }
-      });
-
-      DomApi.prototype.querySelectorAll = function(selector) {
-        return Array.prototype.slice.call(this.node.querySelectorAll(selector));
-      };
-
-      DomApi.prototype.getOwnerRoot = function() {
-        var n = this.node;
-        while (n) {
-          if (n.nodeType === Node.DOCUMENT_FRAGMENT_NODE && n.host) {
-            return n;
-          }
-          n = n.parentNode;
-        }
-      };
-
-      DomApi.prototype.importNode = function(externalNode, deep) {
-        var doc = this.node instanceof Document ? this.node :
-          this.node.ownerDocument;
-        return doc.importNode(externalNode, deep);
-      }
-
-      DomApi.prototype.getDestinationInsertionPoints = function() {
-        var n$ = this.node.getDestinationInsertionPoints && 
-          this.node.getDestinationInsertionPoints();
-        return n$ ? Array.prototype.slice.call(n$) : [];
-      };
-
-      DomApi.prototype.getDistributedNodes = function() {
-        var n$ = this.node.getDistributedNodes && 
-          this.node.getDistributedNodes();
-        return n$ ? Array.prototype.slice.call(n$) : [];
-      };
-
-      DomApi.prototype._distributeParent = function() {};
-
-      var nativeForwards = ['appendChild', 'insertBefore', 
-        'removeChild', 'replaceChild'];
-
-      nativeForwards.forEach(function(forward) {
-        DomApi.prototype[forward] = function() {
-          return this.node[forward].apply(this.node, arguments);
-        };
-      });
-
-      Object.defineProperties(DomApi.prototype, {
-
-        childNodes: {
-          get: function() {
-            return Array.prototype.slice.call(this.node.childNodes);
-          },
-          configurable: true
-        },
-
-        children: {
-          get: function() {
-            return Array.prototype.slice.call(this.node.children);
-          },
-          configurable: true
-        },
-
-        // textContent / innerHTML
-        textContent: {
-          get: function() {
-            return this.node.textContent;
-          },
-          set: function(value) {
-            return this.node.textContent = value;
-          },
-          configurable: true
-        },
-
-        innerHTML: {
-          get: function() {
-            return this.node.innerHTML;
-          },
-          set: function(value) {
-            return this.node.innerHTML = value;
-          },
-          configurable: true
-        }
-
-      });
-
-      var forwardProperties = ['parentNode', 'firstChild', 'lastChild', 
-      'nextSibling', 'previousSibling', 'firstElementChild', 'lastElementChild',
-      'nextElementSibling', 'previousElementSibling'];
-
-      forwardProperties.forEach(function(name) {
-        Object.defineProperty(DomApi.prototype, name, {
-          get: function() {
-            return this.node[name];
-          },
-          configurable: true
-        });
-      });
-
-    }
-
-    var CONTENT = 'content';
-
-    function factory(node, patch) {
-      node = node || document;
-      if (!node.__domApi) {
-        node.__domApi = new DomApi(node, patch);
-      }
-      return node.__domApi;
-    };
-
-    function hasDomApi(node) {
-      return Boolean(node.__domApi);
-    }
-
-    Polymer.dom = function(obj, patch) {
-      if (obj instanceof Event) {
-        return Polymer.EventApi.factory(obj);
-      } else {
-        return factory(obj, patch);
-      }
-    };
-
-    function getLightChildren(node) {
-      var children = node._lightChildren;
-      // TODO(sorvell): it's more correct to use _composedChildren instead of
-      // childNodes here but any trivial failure to use Polymer.dom
-      // will result in an error so we avoid using _composedChildren
-      return children ? children : node.childNodes;
-    }
-
-    function getComposedChildren(node) {
-      if (!node._composedChildren) {
-        node._composedChildren = Array.prototype.slice.call(node.childNodes);
-      }
-      return node._composedChildren;
-    }
-
-    function addToComposedParent(parent, node, ref_node) {
-      var children = getComposedChildren(parent);
-      var i = ref_node ? children.indexOf(ref_node) : -1;
-      if (node.nodeType === Node.DOCUMENT_FRAGMENT_NODE) {
-        var fragChildren = getComposedChildren(node);
-        for (var j=0; j < fragChildren.length; j++) {
-          addNodeToComposedChildren(fragChildren[j], parent, children, i + j);
-        }
-        node._composedChildren = null;
-      } else {
-        addNodeToComposedChildren(node, parent, children, i);
-      }
-    }
-
-    function getComposedParent(node) {
-      return node.__patched ? node._composedParent : node.parentNode;
-    }
-
-    function addNodeToComposedChildren(node, parent, children, i) {
-      node._composedParent = parent;
-      children.splice(i >= 0 ? i : children.length, 0, node);
-    }
-
-    function removeFromComposedParent(parent, node) {
-      node._composedParent = null;
-      if (parent) {
-        var children = getComposedChildren(parent);
-        var i = children.indexOf(node);
-        if (i >= 0) {
-          children.splice(i, 1);
-        }
-      }
-    }
-
-    function saveLightChildrenIfNeeded(node) {
-      // Capture the list of light children. It's important to do this before we
-      // start transforming the DOM into "rendered" state.
-      //
-      // Children may be added to this list dynamically. It will be treated as the
-      // source of truth for the light children of the element. This element's
-      // actual children will be treated as the rendered state once lightChildren
-      // is populated.
-      if (!node._lightChildren) {
-        var c$ = Array.prototype.slice.call(node.childNodes);
-        for (var i=0, l=c$.length, child; (i<l) && (child=c$[i]); i++) {
-          child._lightParent = child._lightParent || node;
-        }
-        node._lightChildren = c$;
-      }
-    }
-
-    function hasInsertionPoint(root) {
-      return Boolean(root && root._insertionPoints.length);
-    }
-
-    var p = Element.prototype;
-    var matchesSelector = p.matches || p.matchesSelector ||
-        p.mozMatchesSelector || p.msMatchesSelector ||
-        p.oMatchesSelector || p.webkitMatchesSelector;
-
-    return {
-      getLightChildren: getLightChildren,
-      getComposedParent: getComposedParent,
-      getComposedChildren: getComposedChildren,
-      removeFromComposedParent: removeFromComposedParent,
-      saveLightChildrenIfNeeded: saveLightChildrenIfNeeded,
-      matchesSelector: matchesSelector,
-      hasInsertionPoint: hasInsertionPoint,
-      ctor: DomApi,
-      factory: factory,
-      hasDomApi: hasDomApi
-    };
-
-  })();
-
-</script>
\ No newline at end of file
+<!--
+@license
+Copyright (c) 2014 The Polymer Project Authors. All rights reserved.
+This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
+The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
+The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
+Code distributed by Google as part of the polymer project is also
+subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
+-->
+<link rel="import" href="settings.html">
+<link rel="import" href="dom-innerHTML.html">
+<script>
+
+  /**
+   * DomApi is a dom manipulation library which is compatible with both
+   * Shady DOM and Shadow DOM. The general usage is
+   * `Polymer.dom(node).method(arguments)` where methods and arguments
+   * match native DOM where possible.
+   */
+  Polymer.DomApi = (function() {
+    'use strict';
+
+    var Settings = Polymer.Settings;
+    var getInnerHTML = Polymer.domInnerHTML.getInnerHTML;
+
+    var nativeInsertBefore = Element.prototype.insertBefore;
+    var nativeRemoveChild = Element.prototype.removeChild;
+    var nativeAppendChild = Element.prototype.appendChild;
+    var nativeCloneNode = Element.prototype.cloneNode;
+    var nativeImportNode = Document.prototype.importNode;
+
+    var DomApi = function(node) {
+      this.node = node;
+      if (this.patch) {
+        this.patch();
+      }
+    };
+
+    // ensure nodes are wrapped if SD polyfill is present
+    if (window.wrap && Settings.useShadow && !Settings.useNativeShadow) {
+      DomApi = function(node) {
+        this.node = wrap(node);
+        if (this.patch) {
+          this.patch();
+        }
+      };
+    }
+
+    DomApi.prototype = {
+
+      flush: function() {
+        Polymer.dom.flush();
+      },
+
+      /**
+       * Check that the given node is a descendant of `this`,
+       * ignoring ShadowDOM boundaries
+       * @param {Node} node
+       * @return {Boolean} true if `node` is a descendant or equal to `this`
+       */
+      deepContains: function(node) {
+        // fast path, use shallow `contains`.
+        if (this.node.contains(node)) {
+          return true;
+        }
+        var n = node;
+
+        // walk from node to `this` or `document`
+        while (n && n !== document && n !== this.node) {
+          n = n.parentNode || n.host;
+        }
+        return n === this.node;
+      },
+
+      _lazyDistribute: function(host) {
+        // note: only try to distribute if the root is not clean; this ensures
+        // we don't distribute before initial distribution
+        if (host.shadyRoot && host.shadyRoot._distributionClean) {
+          host.shadyRoot._distributionClean = false;
+          Polymer.dom.addDebouncer(host.debounce('_distribute',
+            host._distributeContent));
+        }
+      },
+
+      appendChild: function(node) {
+        return this._addNode(node);
+      },
+
+      insertBefore: function(node, ref_node) {
+        return this._addNode(node, ref_node);
+      },
+
+      // cases in which we may not be able to just do standard native call
+      // 1. container has a shadyRoot (needsDistribution IFF the shadyRoot
+      // has an insertion point)
+      // 2. container is a shadyRoot (don't distribute, instead set
+      // container to container.host.
+      // 3. node is <content> (host of container needs distribution)
+      _addNode: function(node, ref_node) {
+        this._removeNodeFromParent(node);
+        var addedInsertionPoint;
+        var root = this.getOwnerRoot();
+        // if a <content> is added, make sure it's parent has logical info.
+        if (root) {
+          addedInsertionPoint = this._maybeAddInsertionPoint(node, this.node);
+        }
+        if (this._nodeHasLogicalChildren(this.node)) {
+          if (ref_node) {
+            var children = this.childNodes;
+            var index = children.indexOf(ref_node);
+            if (index < 0) {
+              throw Error('The ref_node to be inserted before is not a child ' +
+                'of this node');
+            }
+          }
+          this._addLogicalInfo(node, this.node, index);
+        }
+        this._addNodeToHost(node);
+        // if not distributing and not adding to host, do a fast path addition
+        if (!this._maybeDistribute(node, this.node) &&
+          !this._tryRemoveUndistributedNode(node)) {
+          if (ref_node) {
+            // if ref_node is <content> replace with first distributed node
+            ref_node = ref_node.localName === CONTENT ?
+              this._firstComposedNode(ref_node) : ref_node;
+          }
+          // if adding to a shadyRoot, add to host instead
+          var container = this.node._isShadyRoot ? this.node.host : this.node;
+          addToComposedParent(container, node, ref_node);
+          if (ref_node) {
+            nativeInsertBefore.call(container, node, ref_node);
+          } else {
+            nativeAppendChild.call(container, node);
+          }
+        }
+        if (addedInsertionPoint) {
+          this._updateInsertionPoints(root.host);
+        }
+        this.notifyObserver();
+        return node;
+      },
+
+      /**
+        Removes the given `node` from the element's `lightChildren`.
+        This method also performs dom composition.
+      */
+      removeChild: function(node) {
+        if (factory(node).parentNode !== this.node) {
+          console.warn('The node to be removed is not a child of this node',
+            node);
+        }
+        this._removeNodeFromHost(node);
+        if (!this._maybeDistribute(node, this.node)) {
+          // if removing from a shadyRoot, remove form host instead
+          var container = this.node._isShadyRoot ? this.node.host : this.node;
+          // not guaranteed to physically be in container; e.g.
+          // undistributed nodes.
+          if (container === node.parentNode) {
+            removeFromComposedParent(container, node);
+            nativeRemoveChild.call(container, node);
+          }
+        }
+        this.notifyObserver();
+        return node;
+      },
+
+      replaceChild: function(node, ref_node) {
+        this.insertBefore(node, ref_node);
+        this.removeChild(ref_node);
+        return node;
+      },
+
+      _hasCachedOwnerRoot: function(node) {
+        return Boolean(node._ownerShadyRoot !== undefined);
+      },
+
+      getOwnerRoot: function() {
+        return this._ownerShadyRootForNode(this.node);
+      },
+
+      _ownerShadyRootForNode: function(node) {
+        if (!node) {
+          return;
+        }
+        if (node._ownerShadyRoot === undefined) {
+          var root;
+          if (node._isShadyRoot) {
+            root = node;
+          } else {
+            var parent = Polymer.dom(node).parentNode;
+            if (parent) {
+              root = parent._isShadyRoot ? parent :
+                this._ownerShadyRootForNode(parent);
+            } else {
+             root = null;
+            }
+          }
+          node._ownerShadyRoot = root;
+        }
+        return node._ownerShadyRoot;
+      },
+
+      _maybeDistribute: function(node, parent) {
+        // TODO(sorvell): technically we should check non-fragment nodes for
+        // <content> children but since this case is assumed to be exceedingly
+        // rare, we avoid the cost and will address with some specific api
+        // when the need arises.  For now, the user must call
+        // distributeContent(true), which updates insertion points manually
+        // and forces distribution.
+        var fragContent = (node.nodeType === Node.DOCUMENT_FRAGMENT_NODE) &&
+          !node.__noContent && Polymer.dom(node).querySelector(CONTENT);
+        var wrappedContent = fragContent &&
+          (Polymer.dom(fragContent).parentNode.nodeType !==
+          Node.DOCUMENT_FRAGMENT_NODE);
+        var hasContent = fragContent || (node.localName === CONTENT);
+        // There are 2 possible cases where a distribution may need to occur:
+        // 1. <content> being inserted (the host of the shady root where
+        //    content is inserted needs distribution)
+        // 2. children being inserted into parent with a shady root (parent
+        //    needs distribution)
+        if (hasContent) {
+          var root = this._ownerShadyRootForNode(parent);
+          if (root) {
+            var host = root.host;
+            // note, insertion point list update is handled after node
+            // mutations are complete
+            this._lazyDistribute(host);
+          }
+        }
+        var parentNeedsDist = this._parentNeedsDistribution(parent);
+        if (parentNeedsDist) {
+          this._lazyDistribute(parent);
+        }
+        // Return true when distribution will fully handle the composition
+        // Note that if a content was being inserted that was wrapped by a node,
+        // and the parent does not need distribution, return false to allow
+        // the nodes to be added directly, after which children may be
+        // distributed and composed into the wrapping node(s)
+        return parentNeedsDist || (hasContent && !wrappedContent);
+      },
+
+      /* note: parent argument is required since node may have an out
+      of date parent at this point; returns true if a <content> is being added */
+      _maybeAddInsertionPoint: function(node, parent) {
+        var added;
+        if (node.nodeType === Node.DOCUMENT_FRAGMENT_NODE &&
+          !node.__noContent) {
+          var c$ = factory(node).querySelectorAll(CONTENT);
+          for (var i=0, n, np, na; (i<c$.length) && (n=c$[i]); i++) {
+            np = factory(n).parentNode;
+            // don't allow node's parent to be fragment itself
+            if (np === node) {
+              np = parent;
+            }
+            na = this._maybeAddInsertionPoint(n, np);
+            added = added || na;
+          }
+        } else if (node.localName === CONTENT) {
+          saveLightChildrenIfNeeded(parent);
+          saveLightChildrenIfNeeded(node);
+          added = true;
+        }
+        return added;
+      },
+
+      _tryRemoveUndistributedNode: function(node) {
+        if (this.node.shadyRoot) {
+          var parent = getComposedParent(node);
+          if (parent) {
+            nativeRemoveChild.call(parent, node);
+          }
+          return true;
+        }
+      },
+
+      _updateInsertionPoints: function(host) {
+        var i$ = host.shadyRoot._insertionPoints =
+          factory(host.shadyRoot).querySelectorAll(CONTENT);
+        // ensure <content>'s and their parents have logical dom info.
+        for (var i=0, c; i < i$.length; i++) {
+          c = i$[i];
+          saveLightChildrenIfNeeded(c);
+          saveLightChildrenIfNeeded(factory(c).parentNode);
+        }
+      },
+
+      // a node has logical children
+      _nodeHasLogicalChildren: function(node) {
+        return Boolean(node._lightChildren !== undefined);
+      },
+
+      _parentNeedsDistribution: function(parent) {
+        return parent && parent.shadyRoot && hasInsertionPoint(parent.shadyRoot);
+      },
+
+      _removeNodeFromParent: function(node) {
+        // note: we may need to notify and not have logical info so fallback
+        // to composed parentNode.
+        var parent = node._lightParent || node.parentNode;
+        if (parent && hasDomApi(parent)) {
+          factory(parent).notifyObserver();
+        }
+        this._removeNodeFromHost(node, true);
+      },
+
+      // NOTE: if `ensureComposedRemoval` is true then the node should be
+      // removed from its composed parent.
+      _removeNodeFromHost: function(node, ensureComposedRemoval) {
+        // note that it's possible for both the node's host and its parent
+        // to require distribution... both cases are handled here.
+        var hostNeedsDist;
+        var root;
+        var parent = node._lightParent;
+        if (parent) {
+          // distribute node's parent iff needed
+          factory(node)._distributeParent();
+          root = this._ownerShadyRootForNode(node);
+          // remove node from root and distribute it iff needed
+          if (root) {
+            root.host._elementRemove(node);
+            hostNeedsDist = this._removeDistributedChildren(root, node);
+          }
+          this._removeLogicalInfo(node, parent);
+        }
+        this._removeOwnerShadyRoot(node);
+        if (root && hostNeedsDist) {
+          this._updateInsertionPoints(root.host);
+          this._lazyDistribute(root.host);
+        } else if (ensureComposedRemoval) {
+          removeFromComposedParent(getComposedParent(node), node);
+        }
+      },
+
+      _removeDistributedChildren: function(root, container) {
+        var hostNeedsDist;
+        var ip$ = root._insertionPoints;
+        for (var i=0; i<ip$.length; i++) {
+          var content = ip$[i];
+          if (this._contains(container, content)) {
+            var dc$ = factory(content).getDistributedNodes();
+            for (var j=0; j<dc$.length; j++) {
+              hostNeedsDist = true;
+              var node = dc$[j];
+              var parent = node.parentNode;
+              if (parent) {
+                removeFromComposedParent(parent, node);
+                nativeRemoveChild.call(parent, node);
+              }
+            }
+          }
+        }
+        return hostNeedsDist;
+      },
+
+      _contains: function(container, node) {
+        while (node) {
+          if (node == container) {
+            return true;
+          }
+          node = factory(node).parentNode;
+        }
+      },
+
+      // a node being added is always in this same host as this.node.
+      _addNodeToHost: function(node) {
+        var root = this.getOwnerRoot();
+        if (root) {
+          root.host._elementAdd(node);
+        }
+      },
+
+      _addLogicalInfo: function(node, container, index) {
+        var children = factory(container).childNodes;
+        index = index === undefined ? children.length : index;
+        // handle document fragments
+        if (node.nodeType === Node.DOCUMENT_FRAGMENT_NODE) {
+          // NOTE: the act of setting this info can affect patched nodes
+          // getters; therefore capture childNodes before patching.
+          var c$ = Array.prototype.slice.call(node.childNodes);
+          for (var i=0, n; (i<c$.length) && (n=c$[i]); i++) {
+            children.splice(index++, 0, n);
+            n._lightParent = container;
+          }
+        } else {
+          children.splice(index, 0, node);
+          node._lightParent = container;
+        }
+      },
+
+      // NOTE: in general, we expect contents of the lists here to be small-ish
+      // and therefore indexOf to be nbd. Other optimizations can be made
+      // for larger lists (linked list)
+      _removeLogicalInfo: function(node, container) {
+        var children = factory(container).childNodes;
+        var index = children.indexOf(node);
+        if ((index < 0) || (container !== node._lightParent)) {
+          throw Error('The node to be removed is not a child of this node');
+        }
+        children.splice(index, 1);
+        node._lightParent = null;
+      },
+
+      _removeOwnerShadyRoot: function(node) {
+        // optimization: only reset the tree if node is actually in a root
+        if (this._hasCachedOwnerRoot(node)) {
+          var c$ = factory(node).childNodes;
+          for (var i=0, l=c$.length, n; (i<l) && (n=c$[i]); i++) {
+            this._removeOwnerShadyRoot(n);
+          }
+        }
+        node._ownerShadyRoot = undefined;
+      },
+
+      // TODO(sorvell): This will fail if distribution that affects this
+      // question is pending; this is expected to be exceedingly rare, but if
+      // the issue comes up, we can force a flush in this case.
+      _firstComposedNode: function(content) {
+        var n$ = factory(content).getDistributedNodes();
+        for (var i=0, l=n$.length, n, p$; (i<l) && (n=n$[i]); i++) {
+          p$ = factory(n).getDestinationInsertionPoints();
+          // means that we're composed to this spot.
+          if (p$[p$.length-1] === content) {
+            return n;
+          }
+        }
+      },
+
+      // TODO(sorvell): consider doing native QSA and filtering results.
+      querySelector: function(selector) {
+        return this.querySelectorAll(selector)[0];
+      },
+
+      querySelectorAll: function(selector) {
+        return this._query(function(n) {
+          return matchesSelector.call(n, selector);
+        }, this.node);
+      },
+
+      _query: function(matcher, node) {
+        node = node || this.node;
+        var list = [];
+        this._queryElements(factory(node).childNodes, matcher, list);
+        return list;
+      },
+
+      _queryElements: function(elements, matcher, list) {
+        for (var i=0, l=elements.length, c; (i<l) && (c=elements[i]); i++) {
+          if (c.nodeType === Node.ELEMENT_NODE) {
+            this._queryElement(c, matcher, list);
+          }
+        }
+      },
+
+      _queryElement: function(node, matcher, list) {
+        if (matcher(node)) {
+          list.push(node);
+        }
+        this._queryElements(factory(node).childNodes, matcher, list);
+      },
+
+      getDestinationInsertionPoints: function() {
+        return this.node._destinationInsertionPoints || [];
+      },
+
+      getDistributedNodes: function() {
+        return this.node._distributedNodes || [];
+      },
+
+      /*
+        Returns a list of nodes distributed within this element. These can be
+        dom children or elements distributed to children that are insertion
+        points.
+      */
+      queryDistributedElements: function(selector) {
+        var c$ = this.getEffectiveChildNodes();
+        var list = [];
+        for (var i=0, l=c$.length, c; (i<l) && (c=c$[i]); i++) {
+          if ((c.nodeType === Node.ELEMENT_NODE) &&
+              matchesSelector.call(c, selector)) {
+            list.push(c);
+          }
+        }
+        return list;
+      },
+
+      /*
+        Returns a list of effective childNoes within this element. These can be
+        dom child nodes or elements distributed to children that are insertion
+        points.
+      */
+      getEffectiveChildNodes: function() {
+        var list = [];
+        var c$ = this.childNodes;
+        for (var i=0, l=c$.length, c; (i<l) && (c=c$[i]); i++) {
+          if (c.localName === CONTENT) {
+            var d$ = factory(c).getDistributedNodes();
+            for (var j=0; j < d$.length; j++) {
+              list.push(d$[j]);
+            }
+          } else {
+            list.push(c);
+          }
+        }
+        return list;
+      },
+
+      _clear: function() {
+        while (this.childNodes.length) {
+          this.removeChild(this.childNodes[0]);
+        }
+      },
+
+      setAttribute: function(name, value) {
+        this.node.setAttribute(name, value);
+        this._distributeParent();
+      },
+
+      removeAttribute: function(name) {
+        this.node.removeAttribute(name);
+        this._distributeParent();
+      },
+
+      _distributeParent: function() {
+        if (this._parentNeedsDistribution(this.parentNode)) {
+          this._lazyDistribute(this.parentNode);
+        }
+      },
+
+      cloneNode: function(deep) {
+        var n = nativeCloneNode.call(this.node, false);
+        if (deep) {
+          var c$ = this.childNodes;
+          var d = factory(n);
+          for (var i=0, nc; i < c$.length; i++) {
+            nc = factory(c$[i]).cloneNode(true);
+            d.appendChild(nc);
+          }
+        }
+        return n;
+      },
+
+      importNode: function(externalNode, deep) {
+        // for convenience use this node's ownerDoc if the node isn't a document
+        var doc = this.node instanceof Document ? this.node :
+          this.node.ownerDocument;
+        var n = nativeImportNode.call(doc, externalNode, false);
+        if (deep) {
+          var c$ = factory(externalNode).childNodes;
+          var d = factory(n);
+          for (var i=0, nc; i < c$.length; i++) {
+            nc = factory(doc).importNode(c$[i], true);
+            d.appendChild(nc);
+          }
+        }
+        return n;
+      },
+
+      /**
+       * Notifies callers about changes to the element's effective child nodes,
+       * the same list as returned by `getEffectiveChildNodes`.
+       * @param {function} callback The supplied callback is called with an
+       * `info` argument which is an object that provides
+       * the `target` on which the changes occurred, a list of any nodes
+       * added in the `addedNodes` array, and nodes removed in the
+       * `removedNodes` array.
+       * @return {object} Returns a handle which is the argument to
+       * `unobserveNodes`.
+       */
+      observeNodes: function(callback) {
+        if (callback) {
+          if (!this.observer) {
+            this.observer = this.node.localName === CONTENT ?
+              new DomApi.DistributedNodesObserver(this) :
+              new DomApi.EffectiveNodesObserver(this);
+          }
+          return this.observer.addListener(callback);
+        }
+      },
+
+      /**
+       * Stops observing changes to the element's effective child nodes.
+       * @param {object} handle The handle for the callback that should
+       * no longer receive notifications. This handle is returned from
+       * `observeNodes`.
+       */
+      unobserveNodes: function(handle) {
+        if (this.observer) {
+          this.observer.removeListener(handle);
+        }
+      },
+
+      notifyObserver: function() {
+        if (this.observer) {
+          this.observer.notify();
+        }
+      }
+
+    };
+
+    // changes and accessors...
+    if (!Settings.useShadow) {
+
+      Object.defineProperties(DomApi.prototype, {
+
+        childNodes: {
+          get: function() {
+            var c$ = getLightChildren(this.node);
+            return Array.isArray(c$) ? c$ : Array.prototype.slice.call(c$);
+          },
+          configurable: true
+        },
+
+        children: {
+          get: function() {
+            return Array.prototype.filter.call(this.childNodes, function(n) {
+              return (n.nodeType === Node.ELEMENT_NODE);
+            });
+          },
+          configurable: true
+        },
+
+        parentNode: {
+          get: function() {
+            return this.node._lightParent ||
+              getComposedParent(this.node);
+          },
+          configurable: true
+        },
+
+        firstChild: {
+          get: function() {
+            return this.childNodes[0];
+          },
+          configurable: true
+        },
+
+        lastChild: {
+          get: function() {
+            var c$ = this.childNodes;
+            return c$[c$.length-1];
+          },
+          configurable: true
+        },
+
+        nextSibling: {
+          get: function() {
+            var c$ = this.parentNode && factory(this.parentNode).childNodes;
+            if (c$) {
+              return c$[Array.prototype.indexOf.call(c$, this.node) + 1];
+            }
+          },
+          configurable: true
+        },
+
+        previousSibling: {
+          get: function() {
+            var c$ = this.parentNode && factory(this.parentNode).childNodes;
+            if (c$) {
+              return c$[Array.prototype.indexOf.call(c$, this.node) - 1];
+            }
+          },
+          configurable: true
+        },
+
+        firstElementChild: {
+          get: function() {
+            return this.children[0];
+          },
+          configurable: true
+        },
+
+        lastElementChild: {
+          get: function() {
+            var c$ = this.children;
+            return c$[c$.length-1];
+          },
+          configurable: true
+        },
+
+        nextElementSibling: {
+          get: function() {
+            var c$ = this.parentNode && factory(this.parentNode).children;
+            if (c$) {
+              return c$[Array.prototype.indexOf.call(c$, this.node) + 1];
+            }
+          },
+          configurable: true
+        },
+
+        previousElementSibling: {
+          get: function() {
+            var c$ = this.parentNode && factory(this.parentNode).children;
+            if (c$) {
+              return c$[Array.prototype.indexOf.call(c$, this.node) - 1];
+            }
+          },
+          configurable: true
+        },
+
+        // textContent / innerHTML
+        textContent: {
+          get: function() {
+            var nt = this.node.nodeType;
+            if (nt === Node.TEXT_NODE || nt === Node.COMMENT_NODE) {
+              return this.node.textContent;
+            } else {
+              var tc = [];
+              for (var i = 0, cn = this.childNodes, c; c = cn[i]; i++) {
+                if (c.nodeType !== Node.COMMENT_NODE) {
+                  tc.push(c.textContent);
+                }
+              }
+              return tc.join('');
+            }
+          },
+          set: function(text) {
+            var nt = this.node.nodeType;
+            if (nt === Node.TEXT_NODE || nt === Node.COMMENT_NODE) {
+              this.node.textContent = text;
+            } else {
+              this._clear();
+              if (text) {
+                this.appendChild(document.createTextNode(text));
+              }
+            }
+          },
+          configurable: true
+        },
+
+        innerHTML: {
+          get: function() {
+            var nt = this.node.nodeType;
+            if (nt === Node.TEXT_NODE || nt === Node.COMMENT_NODE) {
+              return null;
+            } else {
+              return getInnerHTML(this.node);
+            }
+          },
+          set: function(text) {
+            var nt = this.node.nodeType;
+            if (nt !== Node.TEXT_NODE || nt !== Node.COMMENT_NODE) {
+              this._clear();
+              var d = document.createElement('div');
+              d.innerHTML = text;
+              var c$ = Array.prototype.slice.call(d.childNodes);
+              for (var i=0; i < c$.length; i++) {
+                this.appendChild(c$[i]);
+              }
+            }
+          },
+          configurable: true
+        }
+
+      });
+
+      DomApi.prototype._getComposedInnerHTML = function() {
+        return getInnerHTML(this.node, true);
+      };
+
+
+    } else {
+
+      var forwardMethods = ['cloneNode', 'appendChild', 'insertBefore',
+      'removeChild', 'replaceChild'];
+
+      forwardMethods.forEach(function(name) {
+        DomApi.prototype[name] = function() {
+          return this.node[name].apply(this.node, arguments);
+        }
+      });
+
+      DomApi.prototype.querySelectorAll = function(selector) {
+        return Array.prototype.slice.call(this.node.querySelectorAll(selector));
+      };
+
+      DomApi.prototype.getOwnerRoot = function() {
+        var n = this.node;
+        while (n) {
+          if (n.nodeType === Node.DOCUMENT_FRAGMENT_NODE && n.host) {
+            return n;
+          }
+          n = n.parentNode;
+        }
+      };
+
+      DomApi.prototype.importNode = function(externalNode, deep) {
+        var doc = this.node instanceof Document ? this.node :
+          this.node.ownerDocument;
+        return doc.importNode(externalNode, deep);
+      }
+
+      DomApi.prototype.getDestinationInsertionPoints = function() {
+        var n$ = this.node.getDestinationInsertionPoints &&
+          this.node.getDestinationInsertionPoints();
+        return n$ ? Array.prototype.slice.call(n$) : [];
+      };
+
+      DomApi.prototype.getDistributedNodes = function() {
+        var n$ = this.node.getDistributedNodes &&
+          this.node.getDistributedNodes();
+        return n$ ? Array.prototype.slice.call(n$) : [];
+      };
+
+      DomApi.prototype._distributeParent = function() {};
+
+      var nativeForwards = ['appendChild', 'insertBefore',
+        'removeChild', 'replaceChild'];
+
+      nativeForwards.forEach(function(forward) {
+        DomApi.prototype[forward] = function() {
+          return this.node[forward].apply(this.node, arguments);
+        };
+      });
+
+      Object.defineProperties(DomApi.prototype, {
+
+        childNodes: {
+          get: function() {
+            return Array.prototype.slice.call(this.node.childNodes);
+          },
+          configurable: true
+        },
+
+        children: {
+          get: function() {
+            return Array.prototype.slice.call(this.node.children);
+          },
+          configurable: true
+        },
+
+        // textContent / innerHTML
+        textContent: {
+          get: function() {
+            return this.node.textContent;
+          },
+          set: function(value) {
+            return this.node.textContent = value;
+          },
+          configurable: true
+        },
+
+        innerHTML: {
+          get: function() {
+            return this.node.innerHTML;
+          },
+          set: function(value) {
+            return this.node.innerHTML = value;
+          },
+          configurable: true
+        }
+
+      });
+
+      var forwardProperties = ['parentNode', 'firstChild', 'lastChild',
+      'nextSibling', 'previousSibling', 'firstElementChild', 'lastElementChild',
+      'nextElementSibling', 'previousElementSibling'];
+
+      forwardProperties.forEach(function(name) {
+        Object.defineProperty(DomApi.prototype, name, {
+          get: function() {
+            return this.node[name];
+          },
+          configurable: true
+        });
+      });
+
+    }
+
+    var CONTENT = 'content';
+
+    function factory(node, patch) {
+      node = node || document;
+      if (!node.__domApi) {
+        node.__domApi = new DomApi(node, patch);
+      }
+      return node.__domApi;
+    };
+
+    function hasDomApi(node) {
+      return Boolean(node.__domApi);
+    }
+
+    Polymer.dom = function(obj, patch) {
+      if (obj instanceof Event) {
+        return Polymer.EventApi.factory(obj);
+      } else {
+        return factory(obj, patch);
+      }
+    };
+
+    function getLightChildren(node) {
+      var children = node._lightChildren;
+      // TODO(sorvell): it's more correct to use _composedChildren instead of
+      // childNodes here but any trivial failure to use Polymer.dom
+      // will result in an error so we avoid using _composedChildren
+      return children ? children : node.childNodes;
+    }
+
+    function getComposedChildren(node) {
+      if (!node._composedChildren) {
+        node._composedChildren = Array.prototype.slice.call(node.childNodes);
+      }
+      return node._composedChildren;
+    }
+
+    function addToComposedParent(parent, node, ref_node) {
+      var children = getComposedChildren(parent);
+      var i = ref_node ? children.indexOf(ref_node) : -1;
+      if (node.nodeType === Node.DOCUMENT_FRAGMENT_NODE) {
+        var fragChildren = getComposedChildren(node);
+        for (var j=0; j < fragChildren.length; j++) {
+          addNodeToComposedChildren(fragChildren[j], parent, children, i + j);
+        }
+        node._composedChildren = null;
+      } else {
+        addNodeToComposedChildren(node, parent, children, i);
+      }
+    }
+
+    function getComposedParent(node) {
+      return node.__patched ? node._composedParent : node.parentNode;
+    }
+
+    function addNodeToComposedChildren(node, parent, children, i) {
+      node._composedParent = parent;
+      children.splice(i >= 0 ? i : children.length, 0, node);
+    }
+
+    function removeFromComposedParent(parent, node) {
+      node._composedParent = null;
+      if (parent) {
+        var children = getComposedChildren(parent);
+        var i = children.indexOf(node);
+        if (i >= 0) {
+          children.splice(i, 1);
+        }
+      }
+    }
+
+    function saveLightChildrenIfNeeded(node) {
+      // Capture the list of light children. It's important to do this before we
+      // start transforming the DOM into "rendered" state.
+      //
+      // Children may be added to this list dynamically. It will be treated as the
+      // source of truth for the light children of the element. This element's
+      // actual children will be treated as the rendered state once lightChildren
+      // is populated.
+      if (!node._lightChildren) {
+        var c$ = Array.prototype.slice.call(node.childNodes);
+        for (var i=0, l=c$.length, child; (i<l) && (child=c$[i]); i++) {
+          child._lightParent = child._lightParent || node;
+        }
+        node._lightChildren = c$;
+      }
+    }
+
+    function hasInsertionPoint(root) {
+      return Boolean(root && root._insertionPoints.length);
+    }
+
+    var p = Element.prototype;
+    var matchesSelector = p.matches || p.matchesSelector ||
+        p.mozMatchesSelector || p.msMatchesSelector ||
+        p.oMatchesSelector || p.webkitMatchesSelector;
+
+    return {
+      getLightChildren: getLightChildren,
+      getComposedParent: getComposedParent,
+      getComposedChildren: getComposedChildren,
+      removeFromComposedParent: removeFromComposedParent,
+      saveLightChildrenIfNeeded: saveLightChildrenIfNeeded,
+      matchesSelector: matchesSelector,
+      hasInsertionPoint: hasInsertionPoint,
+      ctor: DomApi,
+      factory: factory,
+      hasDomApi: hasDomApi
+    };
+
+  })();
+
+</script>
diff --git a/test/unit/polymer-dom-elements.html b/test/unit/polymer-dom-elements.html
index 75d2b2b964..0129b71513 100644
--- a/test/unit/polymer-dom-elements.html
+++ b/test/unit/polymer-dom-elements.html
@@ -55,7 +55,7 @@
   Polymer({
     is: 'x-test-no-distribute'
   });
-</script> 
+</script>
 
 <dom-module id="x-distribute">
   <template>
@@ -328,4 +328,21 @@
     }
   });
   </script>
-</dom-module>
\ No newline at end of file
+</dom-module>
+
+<dom-module id="x-deep-contains">
+  <template>
+    <div id="shadowed"></div>
+    <content></content>
+  </template>
+  <script>
+    Polymer({
+      is: 'x-deep-contains',
+      created: function() {
+        var e = document.createElement('div');
+        e.id = 'light';
+        Polymer.dom(this).appendChild(e);
+      }
+    });
+  </script>
+</dom-module>
diff --git a/test/unit/polymer-dom-shadow.html b/test/unit/polymer-dom-shadow.html
index 8e704b3ac0..475a2c9e1e 100644
--- a/test/unit/polymer-dom-shadow.html
+++ b/test/unit/polymer-dom-shadow.html
@@ -53,6 +53,8 @@
   <span>2</span>
 </div>
 
+<x-deep-contains></x-deep-contains>
+
 <script src="polymer-dom.js"></script>
 
 </body>
diff --git a/test/unit/polymer-dom.html b/test/unit/polymer-dom.html
index 16671e5a7d..5d40275ec1 100644
--- a/test/unit/polymer-dom.html
+++ b/test/unit/polymer-dom.html
@@ -53,6 +53,8 @@
   <span>2</span>
 </div>
 
+<x-deep-contains></x-deep-contains>
+
 <script src="polymer-dom.js"></script>
 
 </body>
diff --git a/test/unit/polymer-dom.js b/test/unit/polymer-dom.js
index 09a4bda777..4a61228980 100644
--- a/test/unit/polymer-dom.js
+++ b/test/unit/polymer-dom.js
@@ -632,7 +632,7 @@ suite('Polymer.dom', function() {
     } else {
       testHeight();
     }
-    
+
   });
 
 });
@@ -917,4 +917,21 @@ suite('Polymer.dom non-distributed elements', function() {
     assert.equal(Polymer.dom(document.createElement('div')).getDestinationInsertionPoints().length, 0);
     assert.equal(Polymer.dom(document).getDestinationInsertionPoints().length, 0);
   });
+
+  test('Deep Contains', function() {
+    var el = document.querySelector('x-deep-contains');
+    var shadow = el.$.shadowed;
+    var light = el.querySelector('#light');
+    var disconnected = document.createElement('div');
+    var separate = document.createElement('div');
+    document.body.appendChild(separate);
+
+    assert.equal(Polymer.dom(el).deepContains(el), true, 'Element should deepContain itself');
+    assert.equal(Polymer.dom(el).deepContains(shadow), true, 'Shadowed Child element should be found');
+    assert.equal(Polymer.dom(el).deepContains(light), true, 'Light Child element should be found');
+    assert.equal(Polymer.dom(el).deepContains(disconnected), false, 'Disconnected element should not be found');
+    assert.equal(Polymer.dom(el).deepContains(separate), false, 'Unassociated, attached element should not be found');
+
+    document.body.removeChild(separate);
+  });
 });