DevTools: do not abuse inspector controller for the front-end side plumbing.

Source/bindings/core/v8/custom/V8DevToolsHostCustom.cpp

 /*
  * Copyright (C) 2007-2009 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 146 matching lines @@
         if (windowWrapper.IsEmpty())
             return;
         DOMWindow* window = V8Window::toImpl(windowWrapper);
         document = window ? toLocalDOMWindow(window)->document() : nullptr;
     }
     if (!document || !document->page())
         return;
 
     DevToolsHost* devtoolsHost = V8DevToolsHost::toImpl(info.Holder());
     Vector<ContextMenuItem> items = menu.items();
-    devtoolsHost->showContextMenu(document->page(), static_cast<float>(x->NumberValue()), static_cast<float>(y->NumberValue()), items);
+    devtoolsHost->showContextMenu(static_cast<float>(x->NumberValue()), static_cast<float>(y->NumberValue()), items);
 }
 
 } // namespace blink