Avoids irregular OnMoreData callbacks on Windows using Core Audio

media/audio/win/audio_unified_win.h

 // Copyright (c) 2012 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 MEDIA_AUDIO_WIN_AUDIO_UNIFIED_WIN_H_
 #define MEDIA_AUDIO_WIN_AUDIO_UNIFIED_WIN_H_
 
 #include <Audioclient.h>
 #include <MMDeviceAPI.h>
 
@@ skipping 76 matching lines @@
   // Stops and joins the audio thread in case of an error.
   void StopAndJoinThread(HRESULT err);
 
   // Converts unique endpoint ID to user-friendly device name.
   std::string GetDeviceName(LPCWSTR device_id) const;
 
   // Returns the number of channels the audio engine uses for its internal
   // processing/mixing of shared-mode streams for the default endpoint device.
   int endpoint_channel_count() { return format_.Format.nChannels; }
 
+  bool FillRenderEndpointBufferWithSilence(UINT32* num_written_frames);
+
   // Contains the thread ID of the creating thread.
   base::PlatformThreadId creating_thread_id_;
 
   // Our creator, the audio manager needs to be notified when we close.
   AudioManagerWin* manager_;
 
   // The sharing mode for the streams.
   // Valid values are AUDCLNT_SHAREMODE_SHARED and AUDCLNT_SHAREMODE_EXCLUSIVE
   // where AUDCLNT_SHAREMODE_SHARED is the default.
   AUDCLNT_SHAREMODE share_mode_;
@@ skipping 63 matching lines @@
 
   // Container for sending data to AudioSourceCallback::OnMoreIOData().
   scoped_ptr<AudioBus> capture_bus_;
 
   DISALLOW_COPY_AND_ASSIGN(WASAPIUnifiedStream);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_AUDIO_WIN_AUDIO_UNIFIED_WIN_H_