Enforce marking "override" for functions overriding Blink in components/test_runner/.

components/test_runner/web_test_proxy.cc

 // 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.
 
 #include "components/test_runner/web_test_proxy.h"
 
 #include <cctype>
 
 #include "base/callback_helpers.h"
 #include "base/command_line.h"
@@ skipping 54 matching lines @@
  public:
   CaptureCallback(const base::Callback<void(const SkBitmap&)>& callback);
   virtual ~CaptureCallback();
 
   void set_wait_for_popup(bool wait) { wait_for_popup_ = wait; }
   void set_popup_position(const gfx::Point& position) {
     popup_position_ = position;
   }
 
   // WebCompositeAndReadbackAsyncCallback implementation.
-  virtual void didCompositeAndReadback(const SkBitmap& bitmap);
+  void didCompositeAndReadback(const SkBitmap& bitmap) override;
 
  private:
   base::Callback<void(const SkBitmap&)> callback_;
   SkBitmap main_bitmap_;
   bool wait_for_popup_;
   gfx::Point popup_position_;
 };
 
 class LayoutAndPaintCallback : public blink::WebLayoutAndPaintAsyncCallback {
  public:
   LayoutAndPaintCallback(const base::Closure& callback)
       : callback_(callback), wait_for_popup_(false) {
   }
   virtual ~LayoutAndPaintCallback() {
   }
 
   void set_wait_for_popup(bool wait) { wait_for_popup_ = wait; }
 
   // WebLayoutAndPaintAsyncCallback implementation.
-  virtual void didLayoutAndPaint();
+  void didLayoutAndPaint() override;
 
  private:
   base::Closure callback_;
   bool wait_for_popup_;
 };
 
 class HostMethodTask : public WebMethodTask<WebTestProxyBase> {
  public:
   typedef void (WebTestProxyBase::*CallbackMethodType)();
   HostMethodTask(WebTestProxyBase* object, CallbackMethodType callback)
@@ skipping 1310 matching lines @@
   // to cancel the input method's ongoing composition session.
   if (web_widget_)
     web_widget_->confirmComposition();
 }
 
 blink::WebString WebTestProxyBase::acceptLanguages() {
   return blink::WebString::fromUTF8(accept_languages_);
 }
 
 }  // namespace test_runner