DevTools: do not use Internals for inspector highlight tests.

Source/core/inspector/InspectorDOMAgent.cpp

 /*
  * Copyright (C) 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Google Inc. All rights reserved.
  * Copyright (C) 2009 Joseph Pecoraro
  *
  * 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
@@ skipping 2240 matching lines @@
     if (!renderer) {
         *errorString = "No renderer for node, perhaps orphan or hidden node";
         return;
     }
     while (renderer && !renderer->isDocumentElement() && !renderer->isRelayoutBoundaryForInspector())
         renderer = renderer->container();
     Node* resultNode = renderer ? renderer->generatingNode() : node->ownerDocument();
     *relayoutBoundaryNodeId = pushNodePathToFrontend(resultNode);
 }
 
+void InspectorDOMAgent::getHighlightObjectForTest(ErrorString* errorString, int nodeId, RefPtr<JSONObject>& result)
+{
+    Node* node = assertNode(errorString, nodeId);
+    if (!node)
+        return;
+    result = m_overlay->highlightJSONForNode(node);
+}
+
 PassRefPtr<TypeBuilder::Runtime::RemoteObject> InspectorDOMAgent::resolveNode(Node* node, const String& objectGroup)
 {
     Document* document = node->isDocumentNode() ? &node->document() : node->ownerDocument();
     LocalFrame* frame = document ? document->frame() : nullptr;
     if (!frame)
         return nullptr;
 
     InjectedScript injectedScript = m_injectedScriptManager->injectedScriptFor(ScriptState::forMainWorld(frame));
     if (injectedScript.isEmpty())
         return nullptr;
@@ skipping 25 matching lines @@
     visitor->trace(m_revalidateTask);
     visitor->trace(m_searchResults);
 #endif
     visitor->trace(m_history);
     visitor->trace(m_domEditor);
     visitor->trace(m_listener);
     InspectorBaseAgent::trace(visitor);
 }
 
 } // namespace blink