Merge the Sky Engine changes from the SkyDart branch

sky/engine/core/dom/Element.idl

Index: sky/engine/core/dom/Element.idl
diff --git a/sky/engine/core/dom/Element.idl b/sky/engine/core/dom/Element.idl
index a8ad8771b466e526976884fed27cb966125e593c..47d4b6952dd45d7abe3aad6877939c85417ffce5 100644
--- a/sky/engine/core/dom/Element.idl
+++ b/sky/engine/core/dom/Element.idl
@@ -30,7 +30,7 @@
     boolean hasAttributes();
     sequence<Attr> getAttributes();
 
-    [PerWorldBindings] readonly attribute CSSStyleDeclaration style;
+    readonly attribute CSSStyleDeclaration style;
 
     [Reflect] attribute DOMString id;
     readonly attribute DOMString? localName;
@@ -50,10 +50,10 @@
     void focus();
     void blur();
 
-    [PerWorldBindings] readonly attribute DOMTokenList classList;
+    readonly attribute DOMTokenList classList;
 
     [RaisesException] ShadowRoot ensureShadowRoot();
-    [PerWorldBindings] readonly attribute ShadowRoot shadowRoot;
+    readonly attribute ShadowRoot shadowRoot;
     NodeList getDestinationInsertionPoints();
 
     // CSSOM View Module API