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

chrome/browser/android/foreign_session_helper.h

 // Copyright 2013 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 CHROME_BROWSER_ANDROID_FOREIGN_SESSION_HELPER_H_
 #define CHROME_BROWSER_ANDROID_FOREIGN_SESSION_HELPER_H_
 
 #include <jni.h>
 
 #include "base/android/scoped_java_ref.h"
@@ skipping 19 matching lines @@
   jboolean GetForeignSessions(JNIEnv* env, jobject obj, jobject result);
   jboolean OpenForeignSessionTab(JNIEnv* env,
                                  jobject obj,
                                  jobject j_tab,
                                  jstring session_tag,
                                  jint tab_id,
                                  jint disposition);
   void DeleteForeignSession(JNIEnv* env, jobject obj, jstring session_tag);
 
   // NotificationObserver implemenation
-  virtual void Observe(int type,
-                       const content::NotificationSource& source,
-                       const content::NotificationDetails& details) override;
+  void Observe(int type,
+               const content::NotificationSource& source,
+               const content::NotificationDetails& details) override;
 
   static bool RegisterForeignSessionHelper(JNIEnv* env);
 
  private:
-  virtual ~ForeignSessionHelper();
+  ~ForeignSessionHelper() override;
 
   Profile* profile_;  // weak
   base::android::ScopedJavaGlobalRef<jobject> callback_;
   content::NotificationRegistrar registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(ForeignSessionHelper);
 };
 
 #endif  // CHROME_BROWSER_ANDROID_FOREIGN_SESSION_HELPER_H_