[selectors4] :focus-within should use the flat tree

https://bugs.webkit.org/show_bug.cgi?id=170899

Reviewed by Antti Koivisto.

Source/WebCore:

This has been discussed in the following CSS WG issue:
w3c/csswg-drafts#1135

And the spec has been updated (https://drafts.csswg.org/selectors-4/#the-focus-within-pseudo):
"An element also matches :focus-within if one of its descendants in the flat tree
 (including non-element nodes, such as text nodes) matches the conditions for matching :focus."

Test: imported/w3c/web-platform-tests/css/selectors4/focus-within-shadow-006.html

* dom/Element.cpp:
(WebCore::Element::setFocus): Use "flat tree" ("composed tree" in WebKit)
to set focus-within flag.

LayoutTests:

* TestExpectations: Remove test that is passing now.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@215719 268f45cc-cd09-0410-ab3c-d52691b4dbfc

LayoutTests/ChangeLog

@@ -1,3 +1,12 @@
+2017-04-24  Manuel Rego Casasnovas  <rego@igalia.com>
+
+        [selectors4] :focus-within should use the flat tree
+        https://bugs.webkit.org/show_bug.cgi?id=170899
+
+        Reviewed by Antti Koivisto.
+
+        * TestExpectations: Remove test that is passing now.
+
 2017-04-24  Nan Wang  <n_wang@apple.com>
 
         AX: Crash at WebCore::AXObjectCache::characterOffsetForIndex(int, WebCore::AccessibilityObject const*) + 703

LayoutTests/TestExpectations

@@ -285,7 +285,6 @@ webkit.org/b/169271 imported/w3c/web-platform-tests/css/css-grid-1/grid-items/gr
 
 # selectors4
 webkit.org/b/170900 imported/w3c/web-platform-tests/css/selectors4/focus-within-006.html [ ImageOnlyFailure ]
-webkit.org/b/170899 imported/w3c/web-platform-tests/css/selectors4/focus-within-shadow-006.html [ ImageOnlyFailure ]
 webkit.org/b/64861 imported/w3c/web-platform-tests/css/selectors4/selectors-dir-selector-ltr-001.html [ ImageOnlyFailure ]
 webkit.org/b/64861 imported/w3c/web-platform-tests/css/selectors4/selectors-dir-selector-rtl-001.html [ ImageOnlyFailure ]
 

Source/WebCore/ChangeLog

@@ -1,3 +1,23 @@
+2017-04-24  Manuel Rego Casasnovas  <rego@igalia.com>
+
+        [selectors4] :focus-within should use the flat tree
+        https://bugs.webkit.org/show_bug.cgi?id=170899
+
+        Reviewed by Antti Koivisto.
+
+        This has been discussed in the following CSS WG issue:
+        https://github.com/w3c/csswg-drafts/issues/1135
+
+        And the spec has been updated (https://drafts.csswg.org/selectors-4/#the-focus-within-pseudo):
+        "An element also matches :focus-within if one of its descendants in the flat tree
+         (including non-element nodes, such as text nodes) matches the conditions for matching :focus."
+
+        Test: imported/w3c/web-platform-tests/css/selectors4/focus-within-shadow-006.html
+
+        * dom/Element.cpp:
+        (WebCore::Element::setFocus): Use "flat tree" ("composed tree" in WebKit)
+        to set focus-within flag.
+
 2017-04-24  Wenson Hsieh  <wenson_hsieh@apple.com>
 
         Respect fidelity order when reading web content from item providers

Source/WebCore/dom/Element.cpp

@@ -611,7 +611,7 @@ void Element::setFocus(bool flag)
     document().userActionElements().setFocused(this, flag);
     invalidateStyleForSubtree();
 
-    for (Element* element = this; element; element = element->parentOrShadowHostElement())
+    for (Element* element = this; element; element = element->parentElementInComposedTree())
         element->setHasFocusWithin(flag);
 }