Standardize usage of virtual/override/final in content/browser/

content/browser/fileapi/mock_file_update_observer.h

Index: content/browser/fileapi/mock_file_update_observer.h
diff --git a/content/browser/fileapi/mock_file_update_observer.h b/content/browser/fileapi/mock_file_update_observer.h
index b01c6c96b51d4eea599ca07a80e1579b60266506..78aef9fae253e2bf1fda533f33f0a7de3de25999 100644
--- a/content/browser/fileapi/mock_file_update_observer.h
+++ b/content/browser/fileapi/mock_file_update_observer.h
@@ -19,15 +19,15 @@ namespace storage {
 class MockFileUpdateObserver : public FileUpdateObserver {
  public:
   MockFileUpdateObserver();
-  virtual ~MockFileUpdateObserver();
+  ~MockFileUpdateObserver() override;
 
   // Creates a ChangeObserverList which only contains given |observer|.
   static UpdateObserverList CreateList(MockFileUpdateObserver* observer);
 
   // FileUpdateObserver overrides.
-  virtual void OnStartUpdate(const FileSystemURL& url) override;
-  virtual void OnUpdate(const FileSystemURL& url, int64 delta) override;
-  virtual void OnEndUpdate(const FileSystemURL& url) override;
+  void OnStartUpdate(const FileSystemURL& url) override;
+  void OnUpdate(const FileSystemURL& url, int64 delta) override;
+  void OnEndUpdate(const FileSystemURL& url) override;
 
   void Enable() { is_ready_ = true; }