Fix chromium-style warnings in webrtc/sound/.

webrtc/sound/alsasoundsystem.h

 /*
  *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 16 matching lines @@
   friend class AlsaStream;
   friend class AlsaInputStream;
   friend class AlsaOutputStream;
  public:
   static SoundSystemInterface *Create() {
     return new AlsaSoundSystem();
   }
 
   AlsaSoundSystem();
 
-  virtual ~AlsaSoundSystem();
+  ~AlsaSoundSystem() override;
 
-  virtual bool Init();
-  virtual void Terminate();
+  bool Init() override;
+  void Terminate() override;
 
-  virtual bool EnumeratePlaybackDevices(SoundDeviceLocatorList *devices);
-  virtual bool EnumerateCaptureDevices(SoundDeviceLocatorList *devices);
+  bool EnumeratePlaybackDevices(SoundDeviceLocatorList *devices) override;
+  bool EnumerateCaptureDevices(SoundDeviceLocatorList *devices) override;
 
-  virtual bool GetDefaultPlaybackDevice(SoundDeviceLocator **device);
-  virtual bool GetDefaultCaptureDevice(SoundDeviceLocator **device);
+  bool GetDefaultPlaybackDevice(SoundDeviceLocator **device) override;
+  bool GetDefaultCaptureDevice(SoundDeviceLocator **device) override;
 
-  virtual SoundOutputStreamInterface *OpenPlaybackDevice(
+  SoundOutputStreamInterface *OpenPlaybackDevice(
       const SoundDeviceLocator *device,
-      const OpenParams &params);
-  virtual SoundInputStreamInterface *OpenCaptureDevice(
+      const OpenParams &params) override;
+  SoundInputStreamInterface *OpenCaptureDevice(
       const SoundDeviceLocator *device,
-      const OpenParams &params);
+      const OpenParams &params) override;
 
-  virtual const char *GetName() const;
+  const char *GetName() const override;
 
  private:
   bool IsInitialized() { return initialized_; }
 
   bool EnumerateDevices(SoundDeviceLocatorList *devices,
                         bool capture_not_playback);
 
   bool GetDefaultDevice(SoundDeviceLocator **device);
 
   static size_t FrameSize(const OpenParams &params);
@@ skipping 28 matching lines @@
 
   bool initialized_;
   AlsaSymbolTable symbol_table_;
 
   RTC_DISALLOW_COPY_AND_ASSIGN(AlsaSoundSystem);
 };
 
 }  // namespace rtc
 
 #endif  // WEBRTC_SOUND_ALSASOUNDSYSTEM_H_