add audio-buffer-size command line flag support to the input audio for all the platforms

media/audio/audio_manager_base.h

Index: media/audio/audio_manager_base.h
diff --git a/media/audio/audio_manager_base.h b/media/audio/audio_manager_base.h
index bc13ee5a1677b46c89d08d47321b23bcd59606d8..77b49bc39ef7fcb16874ed5fe9826d5fcf8cda75 100644
--- a/media/audio/audio_manager_base.h
+++ b/media/audio/audio_manager_base.h
@@ -23,6 +23,7 @@
 
 namespace media {
 
+class AudioInputProxy;
 class AudioOutputDispatcher;
 
 // AudioManagerBase provides AudioManager functions common for all platforms.
@@ -150,6 +151,17 @@ class MEDIA_EXPORT AudioManagerBase : public AudioManager {
       const std::string& output_device_id,
       const AudioParameters& input_params) = 0;
 
+  // Returns the preferred hardware audio output parameters for opening input
+  // streams. If the users inject a valid |input_params|, each AudioManager
+  // will decide if they should return the values from |input_params| or the
+  // default hardware values. If the |input_params| is invalid, it will return
+  // the default hardware audio parameters.
+  // If |input_device_id| is empty, the implementation must treat that as
+  // a request for the default output device.
+  virtual AudioParameters GetPreferredInputStreamParameters(
+      const std::string& input_device_id,
+      const AudioParameters& input_params) = 0;
+
   // Returns the ID of the default audio output device.
   // Implementations that don't yet support this should return an empty string.
   virtual std::string GetDefaultOutputDeviceID();
@@ -157,12 +169,18 @@ class MEDIA_EXPORT AudioManagerBase : public AudioManager {
  private:
   struct DispatcherParams;
   typedef ScopedVector<DispatcherParams> AudioOutputDispatchers;
+  typedef ScopedVector<AudioInputProxy> AudioInputProxies;
 
   class CompareByParams;
 
   // Called by Shutdown().
   void ShutdownOnAudioThread();
 
+  // Helper for MakeAudioInputStream() to get the supported hardware
+  // format for the new stream.
+  AudioParameters GetSupportedInputHardwareParameters(
+      const std::string& device_id, const AudioParameters& preferred_params);
+
   // Max number of open output streams, modified by
   // SetMaxOutputStreamsAllowed().
   int max_num_output_streams_;
@@ -187,10 +205,14 @@ class MEDIA_EXPORT AudioManagerBase : public AudioManager {
   // and GetTaskRunner() starts returning NULL.
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
 
-  // Map of cached AudioOutputDispatcher instances.  Must only be touched
-  // from the audio thread (no locking).
+  // Vector of cached AudioOutputDispatcher instances.  Must only be touched
+  // on the audio thread (no locking).
   AudioOutputDispatchers output_dispatchers_;
 
+  // Vector of cached AudioInputProxy instances.  Must only be touched on
+  // the audio thread.
+  AudioInputProxies input_proxies_;
+
   // Proxy for creating AudioLog objects.
   AudioLogFactory* const audio_log_factory_;