Remove Downcasting RVContextMenuBase in ContextMenuDeleagate implementations.

components/renderer_context_menu/context_menu_delegate.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef COMPONENTS_RENDERER_CONTEXT_MENU_CONTEXT_MENU_DELEGATE_H_
 #define COMPONENTS_RENDERER_CONTEXT_MENU_CONTEXT_MENU_DELEGATE_H_
 
 #include "base/memory/scoped_ptr.h"
 
-class RenderViewContextMenu;
+class RenderViewContextMenuBase;
 
 namespace content {
 class WebContents;
 struct ContextMenuParams;
 }
 
 // A ContextMenuDelegate can build and show renderer context menu.
 class ContextMenuDelegate {
  public:
   explicit ContextMenuDelegate(content::WebContents* web_contents);
   virtual ~ContextMenuDelegate();
 
   static ContextMenuDelegate* FromWebContents(
       content::WebContents* web_contents);
 
   // Builds and returns a context menu for a context specified by |params|.
   // The returned value can be used to display the context menu.
-  virtual scoped_ptr<RenderViewContextMenu> BuildMenu(
+  virtual scoped_ptr<RenderViewContextMenuBase> BuildMenu(
       content::WebContents* web_contents,
       const content::ContextMenuParams& params) = 0;
 
   // Displays the context menu.
-  virtual void ShowMenu(scoped_ptr<RenderViewContextMenu> menu) = 0;
+  virtual void ShowMenu(scoped_ptr<RenderViewContextMenuBase> menu) = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ContextMenuDelegate);
 };
 
 #endif  // COMPONENTS_RENDERER_CONTEXT_MENU_CONTEXT_MENU_DELEGATE_H_