[Chromoting] Audio playback won't work after switching default playback device

remoting/host/audio_capturer_win.h

Index: remoting/host/audio_capturer_win.h
diff --git a/remoting/host/audio_capturer_win.h b/remoting/host/audio_capturer_win.h
index d53920a43d9284f6b4ebd8f7d8f5f626b568a87e..ec91d05d812f75ae0802b653145a0d97c937c161 100644
--- a/remoting/host/audio_capturer_win.h
+++ b/remoting/host/audio_capturer_win.h
@@ -31,6 +31,16 @@ class AudioCapturerWin : public AudioCapturer {
   bool Start(const PacketCapturedCallback& callback) override;
 
  private:
+  // The implementation of IMMNotificationClient, to set
+  // default_audio_device_changed_ in OnDefaultDeviceChanged function.
+  class MMNotificationClient;
+  friend class MMNotificationClient;
+
+  // Initializes default audio device related components. These components must
+  // be recreated once the default audio device changed. Returns false if
+  // initialization failed.
+  bool Initialize();
+
   // Receives all packets from the audio capture endpoint buffer and pushes them
   // to the network.
   void DoCapture();
@@ -55,11 +65,17 @@ class AudioCapturerWin : public AudioCapturer {
   AudioSilenceDetector silence_detector_;
 
   base::win::ScopedCoMem<WAVEFORMATEX> wave_format_ex_;
+  base::win::ScopedComPtr<IMMDeviceEnumerator> mm_device_enumerator_;
   base::win::ScopedComPtr<IAudioCaptureClient> audio_capture_client_;
   base::win::ScopedComPtr<IAudioClient> audio_client_;
   base::win::ScopedComPtr<IMMDevice> mm_device_;
   base::win::ScopedComPtr<IAudioEndpointVolume> audio_volume_;
 
+  // Whether the default audio device has been changed recently. If this value
+  // is true, we need to recreate all audio components;
+  bool default_audio_device_changed_;

[Sergey Ulanov, 2016/07/18 23:09:24]

 = false;

[Hzj_jie, 2016/07/19 02:36:40]

Done.

+  const std::unique_ptr<MMNotificationClient> notificator_;
+
   HRESULT last_capture_error_;
 
   base::ThreadChecker thread_checker_;