Update {virtual,override,final} to follow C++11 style.

content/browser/renderer_host/render_widget_host_impl.h

 // Copyright (c) 2012 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 CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_IMPL_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_IMPL_H_
 
 #include <deque>
 #include <list>
 #include <map>
@@ skipping 122 matching lines @@
   void NotifyTextDirection() override;
   void Focus() override;
   void Blur() override;
   void SetActive(bool active) override;
   void CopyFromBackingStore(const gfx::Rect& src_rect,
                             const gfx::Size& accelerated_dst_size,
                             ReadbackRequestCallback& callback,
                             const SkColorType color_type) override;
   bool CanCopyFromBackingStore() override;
 #if defined(OS_ANDROID)
-  virtual void LockBackingStore() override;
-  virtual void UnlockBackingStore() override;
+  void LockBackingStore() override;
+  void UnlockBackingStore() override;
 #endif
   void ForwardMouseEvent(const blink::WebMouseEvent& mouse_event) override;
   void ForwardWheelEvent(const blink::WebMouseWheelEvent& wheel_event) override;
   void ForwardKeyboardEvent(const NativeWebKeyboardEvent& key_event) override;
   RenderProcessHost* GetProcess() const override;
   int GetRoutingID() const override;
   RenderWidgetHostView* GetView() const override;
   bool IsLoading() const override;
   bool IsRenderView() const override;
   void ResizeRectChanged(const gfx::Rect& new_rect) override;
@@ skipping 687 matching lines @@
   bool owned_by_render_frame_host_;
 
   base::WeakPtrFactory<RenderWidgetHostImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_IMPL_H_