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

content/renderer/device_sensors/device_sensor_event_pump.h

 // Copyright 2014 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_DEVICE_SENSORS_DEVICE_SENSOR_EVENT_PUMP_H_
 #define CONTENT_RENDERER_DEVICE_SENSORS_DEVICE_SENSOR_EVENT_PUMP_H_
 
 #include "base/memory/shared_memory.h"
 #include "base/time/time.h"
 #include "base/timer/timer.h"
 #include "content/public/renderer/platform_event_observer.h"
 
 namespace content {
 
 template <typename ListenerType>
 class CONTENT_EXPORT DeviceSensorEventPump
     : NON_EXPORTED_BASE(public PlatformEventObserver<ListenerType>) {
  public:
   // Default rate for firing events.
   static const int kDefaultPumpFrequencyHz = 60;
   static const int kDefaultPumpDelayMicroseconds =
       base::Time::kMicrosecondsPerSecond / kDefaultPumpFrequencyHz;
 
   // PlatformEventObserver
-  virtual void Start(blink::WebPlatformEventListener* listener) override {
+  void Start(blink::WebPlatformEventListener* listener) override {
     DVLOG(2) << "requested start";
 
     if (state_ != STOPPED)
       return;
 
     DCHECK(!timer_.IsRunning());
 
     PlatformEventObserver<ListenerType>::Start(listener);
     state_ = PENDING_START;
   }
 
-  virtual void Stop() override {
+  void Stop() override {
     DVLOG(2) << "stop";
 
     if (state_ == STOPPED)
       return;
 
     DCHECK((state_ == PENDING_START && !timer_.IsRunning()) ||
         (state_ == RUNNING && timer_.IsRunning()));
 
     if (timer_.IsRunning())
       timer_.Stop();
     PlatformEventObserver<ListenerType>::Stop();
     state_ = STOPPED;
   }
 
  protected:
   explicit DeviceSensorEventPump(RenderThread* thread)
       : PlatformEventObserver<ListenerType>(thread),
         pump_delay_microseconds_(kDefaultPumpDelayMicroseconds),
         state_(STOPPED) {}
 
-  virtual ~DeviceSensorEventPump() {
+  ~DeviceSensorEventPump() override {
     PlatformEventObserver<ListenerType>::StopIfObserving();
   }
 
   // The pump is a tri-state automaton with allowed transitions as follows:
   // STOPPED -> PENDING_START
   // PENDING_START -> RUNNING
   // PENDING_START -> STOPPED
   // RUNNING -> STOPPED
   enum PumpState {
       STOPPED,
@@ skipping 24 matching lines @@
   int pump_delay_microseconds_;
   PumpState state_;
   base::RepeatingTimer<DeviceSensorEventPump> timer_;
 
   DISALLOW_COPY_AND_ASSIGN(DeviceSensorEventPump);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_DEVICE_SENSORS_DEVICE_SENSOR_EVENT_PUMP_H_