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

android_webview/common/aw_content_client.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 ANDROID_WEBVIEW_COMMON_AW_CONTENT_CLIENT_H_
 #define ANDROID_WEBVIEW_COMMON_AW_CONTENT_CLIENT_H_
 
 #include "content/public/common/content_client.h"
 
 #include "base/compiler_specific.h"
 
 namespace android_webview {
 
 std::string GetUserAgent();
 
 class AwContentClient : public content::ContentClient {
  public:
   // ContentClient implementation.
-  virtual std::string GetProduct() const override;
-  virtual std::string GetUserAgent() const override;
-  virtual base::string16 GetLocalizedString(int message_id) const override;
-  virtual base::StringPiece GetDataResource(
+  std::string GetProduct() const override;
+  std::string GetUserAgent() const override;
+  base::string16 GetLocalizedString(int message_id) const override;
+  base::StringPiece GetDataResource(
       int resource_id,
       ui::ScaleFactor scale_factor) const override;
-  virtual bool CanSendWhileSwappedOut(const IPC::Message* message) override;
+  bool CanSendWhileSwappedOut(const IPC::Message* message) override;
 };
 
 }  // namespace android_webview
 
 #endif  // ANDROID_WEBVIEW_COMMON_AW_CONTENT_CLIENT_H_