Standardize usage of virtual/override/final in remoting/

remoting/host/local_input_monitor_mac.mm

Index: remoting/host/local_input_monitor_mac.mm
diff --git a/remoting/host/local_input_monitor_mac.mm b/remoting/host/local_input_monitor_mac.mm
index 8ffdb72c3c567f078b1fa47a84fe05eaeb431d95..d4256587df6a9b9bef908c6edff2c6086d0d6716 100644
--- a/remoting/host/local_input_monitor_mac.mm
+++ b/remoting/host/local_input_monitor_mac.mm
@@ -43,7 +43,7 @@ class LocalInputMonitorMac : public base::NonThreadSafe,
       scoped_refptr<base::SingleThreadTaskRunner> caller_task_runner,
       scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner,
       base::WeakPtr<ClientSessionControl> client_session_control);
-  virtual ~LocalInputMonitorMac();
+  ~LocalInputMonitorMac() override;
 
  private:
   // The actual implementation resides in LocalInputMonitorMac::Core class.
@@ -168,15 +168,14 @@ class LocalInputMonitorMac::Core
 
  private:
   friend class base::RefCountedThreadSafe<Core>;
-  virtual ~Core();
+  ~Core() override;
 
   void StartOnUiThread();
   void StopOnUiThread();
 
   // EventHandler interface.
-  virtual void OnLocalMouseMoved(
-      const webrtc::DesktopVector& position) override;
-  virtual void OnDisconnectShortcut() override;
+  void OnLocalMouseMoved(const webrtc::DesktopVector& position) override;
+  void OnDisconnectShortcut() override;
 
   // Task runner on which public methods of this class must be called.
   scoped_refptr<base::SingleThreadTaskRunner> caller_task_runner_;