Move the logic to retrieve the WebPluginContainer to LocalFrame and Node.

third_party/WebKit/Source/web/WebFrameWidgetImpl.h

 /*
  * Copyright (C) 2014 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 171 matching lines @@
   WebInputEventResult HandleGestureEvent(const WebGestureEvent&) override;
   WebInputEventResult HandleKeyEvent(const WebKeyboardEvent&) override;
   WebInputEventResult HandleCharEvent(const WebKeyboardEvent&) override;
 
   // This method returns the focused frame belonging to this WebWidget, that
   // is, a focused frame with the same local root as the one corresponding
   // to this widget. It will return nullptr if no frame is focused or, the
   // focused frame has a different local root.
   LocalFrame* FocusedLocalFrameInWidget() const;
 
-  WebPlugin* FocusedPluginIfInputMethodSupported(LocalFrame*) const;
-
   LocalFrame* FocusedLocalFrameAvailableForIme() const;
 
   CompositorMutatorImpl& Mutator();
 
   WebWidgetClient* client_;
 
   // WebFrameWidget is associated with a subtree of the frame tree,
   // corresponding to a maximal connected tree of LocalFrames. This member
   // points to the root of that subtree.
   Member<WebLocalFrameImpl> local_root_;
@@ skipping 37 matching lines @@
 
 DEFINE_TYPE_CASTS(WebFrameWidgetImpl,
                   WebFrameWidgetBase,
                   widget,
                   widget->ForSubframe(),
                   widget.ForSubframe());
 
 }  // namespace blink
 
 #endif