Enforce marking "override" for functions overriding Blink.

content/renderer/vr/vr_dispatcher.h

 // Copyright 2015 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 CONTENT_RENDERER_VR_DISPATCHER_H_
 #define CONTENT_RENDERER_VR_DISPATCHER_H_
 
 #include <vector>
 
 #include "base/id_map.h"
 #include "content/common/vr_service.mojom.h"
 #include "third_party/WebKit/public/platform/WebVector.h"
 #include "third_party/WebKit/public/platform/modules/vr/WebVR.h"
 #include "third_party/WebKit/public/platform/modules/vr/WebVRClient.h"
 
 namespace content {
 
 class ServiceRegistry;
 
 class VRDispatcher : NON_EXPORTED_BASE(public blink::WebVRClient) {
  public:
   explicit VRDispatcher(ServiceRegistry* service_registry);
-  ~VRDispatcher();
+  ~VRDispatcher() override;
 
   // blink::WebVRClient implementation.
   void getDevices(blink::WebVRGetDevicesCallback* callback) override;
 
   void getSensorState(unsigned int index,
                       blink::WebHMDSensorState& state) override;
 
   void resetSensor(unsigned int index) override;
 
  private:
@@ skipping 12 matching lines @@
 
   ServiceRegistry* service_registry_;
   VRServicePtr vr_service_;
 
   DISALLOW_COPY_AND_ASSIGN(VRDispatcher);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_VR_DISPATCHER_H_