Allow touch adjustment to return Shadow DOM node.

Source/core/testing/Internals.cpp

 /*
  * 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 618 matching lines @@
 ShadowRoot* Internals::youngerShadowRoot(Node* shadow, ExceptionState& exceptionState)
 {
     if (!shadow || !shadow->isShadowRoot()) {
         exceptionState.throwDOMException(InvalidAccessError, "The node provided is not a valid shadow root.");
         return 0;
     }
 
     return toShadowRoot(shadow)->youngerShadowRoot();
 }
 
+Element* Internals::shadowHost(Node* node, ExceptionState& exceptionState)
+{
+    if (!node) {
+        exceptionState.throwDOMException(InvalidAccessError, ExceptionMessages::argumentNullOrIncorrectType(1, "Node"));
+        return 0;
+    }
+
+    return node->shadowHost();
+
+}
+
 String Internals::shadowRootType(const Node* root, ExceptionState& exceptionState) const
 {
     if (!root || !root->isShadowRoot()) {
         exceptionState.throwDOMException(InvalidAccessError, "The node provided is not a valid shadow root.");
         return String();
     }
 
     switch (toShadowRoot(root)->type()) {
     case ShadowRoot::UserAgentShadowRoot:
         return String("UserAgentShadowRoot");
@@ skipping 1701 matching lines @@
     }
     networkStateNotifier().setWebConnectionTypeForTest(webtype);
 }
 
 unsigned Internals::countHitRegions(CanvasRenderingContext2D* context)
 {
     return context->hitRegionsCount();
 }
 
 } // namespace WebCore