fix(isElement): reduce false-positives in isElement tests

Complimentary change to match changed $parse behaviour.

Author: caitp

src/Angular.js

@@ -601,7 +601,7 @@ var trim = (function() {
 function isElement(node) {
   return !!(node &&
     (node.nodeName  // we are a direct element
-    || (node.on && node.find)));  // we have an on and find method part of jQuery API
+    || (node.prop && node.attr && node.find)));  // we have an on and find method part of jQuery API
 }
 
 /**

test/AngularSpec.js

@@ -1127,5 +1127,25 @@ describe('angular', function() {
         expect(result).toEqual(expected[idx]);
       });
     }));
+
+    // Issue #4805
+    it('should return false for objects resembling a Backbone Collection', function() {
+      // Backbone stuff is sort of hard to mock, if you have a better way of doing this,
+      // please fix this.
+      var fakeBackboneCollection = {
+        children: [{}, {}, {}],
+        find: function() {},
+        on: function() {},
+        off: function() {},
+        bind: function() {}
+      };
+      expect(isElement(fakeBackboneCollection)).toBe(false);
+    });
+
+    it('should return false for arrays with node-like properties', function() {
+      var array = [1,2,3];
+      array.on = true;
+      expect(isElement(array)).toBe(false);
+    });
   });
 });