Revert of Remove scoped styles.

Source/core/testing/Internals.idl

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  * Copyright (C) 2013 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 26 matching lines @@
     boolean isLoadingFromMemoryCache(DOMString url);
 
     void crash();
 
     void setStyleResolverStatsEnabled(boolean enabled);
     [RaisesException] DOMString styleResolverStatsReport();
     [RaisesException] DOMString styleResolverStatsTotalsReport();
 
     [RaisesException] boolean isSharingStyle(Element element1, Element element2);
 
+    [RaisesException] unsigned long numberOfScopedHTMLStyleChildren(Node scope);
     [RaisesException] CSSStyleDeclaration computedStyleIncludingVisitedInfo(Node node);
 
     [RaisesException] ShadowRoot shadowRoot(Element host);
     [RaisesException] ShadowRoot youngestShadowRoot(Element host);
     [RaisesException] ShadowRoot oldestShadowRoot(Element host);
     [RaisesException] ShadowRoot youngerShadowRoot(Node root);
 
     [RaisesException] DOMString shadowRootType(Node root);
     [RaisesException] boolean hasShadowInsertionPoint(Node root);
     [RaisesException] boolean hasContentElement(Node root);
@@ skipping 216 matching lines @@
 
     DOMString textSurroundingNode(Node node, long x, long y, unsigned long maxLength);
 
     void setFocused(boolean focused);
 
     // These functions are for testing NetInfo. You must call setNetworkStateNotifierTestOnly(true)
     // before calling setNetworkConnectionInfo.
     void setNetworkStateNotifierTestOnly(boolean testOnly);
     [RaisesException] void setNetworkConnectionInfo(DOMString type);
 };