Cleanup: Add more conversion helpers for usage.

Source/web/WebDevToolsAgentImpl.cpp

 /*
  * Copyright (C) 2010-2011 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 659 matching lines @@
     m_webViewImpl->addPageOverlay(this, OverlayZOrders::highlight);
 }
 
 void WebDevToolsAgentImpl::hideHighlight()
 {
     m_webViewImpl->removePageOverlay(this);
 }
 
 bool WebDevToolsAgentImpl::sendMessageToFrontend(const String& message)
 {
-    WebDevToolsAgentImpl* devToolsAgent = static_cast<WebDevToolsAgentImpl*>(m_webViewImpl->devToolsAgent());
+    WebDevToolsAgentImpl* devToolsAgent = toWebDevToolsAgentImpl(m_webViewImpl->devToolsAgent());
     if (!devToolsAgent)
         return false;
     m_client->sendMessageToInspectorFrontend(message);
     return true;
 }
 
 void WebDevToolsAgentImpl::updateInspectorStateCookie(const String& state)
 {
     m_client->saveAgentRuntimeState(state);
 }
@@ skipping 69 matching lines @@
         || commandName == InspectorBackendDispatcher::commandNames[InspectorBackendDispatcher::kProfiler_getCPUProfileCmd]
         || commandName == InspectorBackendDispatcher::commandNames[InspectorBackendDispatcher::kHeapProfiler_getHeapSnapshotCmd];
 }
 
 void WebDevToolsAgent::processPendingMessages()
 {
     PageScriptDebugServer::shared().runPendingTasks();
 }
 
 } // namespace WebKit