Allow touch adjustment to return Shadow DOM node.

Source/core/testing/Internals.cpp

Index: Source/core/testing/Internals.cpp
diff --git a/Source/core/testing/Internals.cpp b/Source/core/testing/Internals.cpp
index 7b4715a499a2abc953f9a07590211c7ebf78e0d3..d1e13c5f44484098917286f1c8fb1322e5f5d7cb 100644
--- a/Source/core/testing/Internals.cpp
+++ b/Source/core/testing/Internals.cpp
@@ -636,6 +636,17 @@ ShadowRoot* Internals::youngerShadowRoot(Node* shadow, ExceptionState& exception
     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()) {