Remove "high"-latency audio code path

content/common/media/audio_messages.h

 // Copyright (c) 2011 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.
 
 // IPC messages for the audio.
 // Multiply-included message file, hence no include guard.
 
 #include "base/basictypes.h"
 #include "base/shared_memory.h"
 #include "base/sync_socket.h"
@@ skipping 18 matching lines @@
   IPC_STRUCT_TRAITS_MEMBER(format)
   IPC_STRUCT_TRAITS_MEMBER(channel_layout)
   IPC_STRUCT_TRAITS_MEMBER(sample_rate)
   IPC_STRUCT_TRAITS_MEMBER(bits_per_sample)
   IPC_STRUCT_TRAITS_MEMBER(samples_per_packet)
   IPC_STRUCT_TRAITS_MEMBER(channels)
 IPC_STRUCT_TRAITS_END()
 
 // Messages sent from the browser to the renderer.
 
-// Sent by AudioRendererHost to renderer to request an audio packet.
-IPC_MESSAGE_CONTROL2(AudioMsg_RequestPacket,
-                     int /* stream id */,
-                     AudioBuffersState)
-
-// Tell the renderer process that the audio stream has been created, renderer
-// process would be given a ShareMemoryHandle that it should write to from
-// then on.
-IPC_MESSAGE_CONTROL3(AudioMsg_NotifyStreamCreated,
-                     int /* stream id */,
-                     base::SharedMemoryHandle /* handle */,
-                     uint32 /* length */)
-
 // Tell the renderer process that a low latency audio stream has been created,
 // renderer process would be given a SyncSocket that it should write to from
 // then on.
 #if defined(OS_WIN)
 IPC_MESSAGE_CONTROL4(AudioMsg_NotifyLowLatencyStreamCreated,

[henrika (OOO until Aug 14), 2012/01/29 20:54:00]

Why not rename this to _NotifyStreamCreated and remove usage of "low-latency"?

[vrk (LEFT CHROMIUM), 2012/01/31 23:53:08]

Ah, no reason! I was just going to do the rename in follow-up CL to make things
less confusing. But looks like you and scherkus prefer to do the rename in this
CL, so Done!

Also, it looks like the AudioInput messages and classes have "LowLatency" in the
name as well, and it doesn't look like there's an alternative (i.e.
non-low-latency) path there, either. Do you know why LowLatency is kept there,
or should a similar clean-up be done for AudioInput?

[henrika (OOO until Aug 14), 2012/02/01 13:11:29]

The SpeechInput API are still using the "old" path and e.g. WebRTC & Pepper the
low-latency version. Hence, we need to keep both alternatives.

I am working a refactoring AudioInputController right now and will make more
changes in this area. In short, I can take care of the capture parts. Just let
me know if you see something that needs attention.

[vrk (LEFT CHROMIUM), 2012/02/02 21:05:41]

Awesome, sounds great! Will do if I run into anything :)

                      int /* stream id */,
                      base::SharedMemoryHandle /* handle */,
                      base::SyncSocket::Handle /* socket handle */,
                      uint32 /* length */)
 #else
 IPC_MESSAGE_CONTROL4(AudioMsg_NotifyLowLatencyStreamCreated,
                      int /* stream id */,
                      base::SharedMemoryHandle /* handle */,
                      base::FileDescriptor /* socket handle */,
                      uint32 /* length */)
@@ skipping 35 matching lines @@
                      int /* stream id */,
                      double /* volume */)
 
 IPC_MESSAGE_CONTROL2(AudioInputMsg_NotifyDeviceStarted,
                      int /* stream id */,
                      std::string /* device_id */)
 
 // Messages sent from the renderer to the browser.
 
 // Request that got sent to browser for creating an audio output stream
-IPC_MESSAGE_CONTROL3(AudioHostMsg_CreateStream,
+IPC_MESSAGE_CONTROL2(AudioHostMsg_CreateStream,
                      int /* stream_id */,
-                     AudioParameters /* params */,
-                     bool /* low-latency */)
+                     AudioParameters /* params */)
 
 // Request that got sent to browser for creating an audio input stream
 IPC_MESSAGE_CONTROL4(AudioInputHostMsg_CreateStream,
                      int /* stream_id */,
                      AudioParameters /* params */,
                      bool /* low-latency */,
                      std::string /* device_id */)
 
-// Tell the browser the audio buffer prepared for stream (stream_id) is
-// filled and is ready to be consumed.
-IPC_MESSAGE_CONTROL2(AudioHostMsg_NotifyPacketReady,
-                     int /* stream_id */,
-                     uint32 /* packet size */)
-
 // Start buffering and play the audio stream specified by stream_id.
 IPC_MESSAGE_CONTROL1(AudioHostMsg_PlayStream,
                      int /* stream_id */)
 
 // Start recording the audio input stream specified by stream_id.
 IPC_MESSAGE_CONTROL1(AudioInputHostMsg_RecordStream,
                      int /* stream_id */)
 
 // Pause the audio stream specified by stream_id.
 IPC_MESSAGE_CONTROL1(AudioHostMsg_PauseStream,
                      int /* stream_id */)
 
 // Discard all buffered audio data for the specified audio stream.
 IPC_MESSAGE_CONTROL1(AudioHostMsg_FlushStream,
                      int /* stream_id */)
 
 // Close an audio stream specified by stream_id.
 IPC_MESSAGE_CONTROL1(AudioHostMsg_CloseStream,
                      int /* stream_id */)
 
 // Close an audio input stream specified by stream_id.
 IPC_MESSAGE_CONTROL1(AudioInputHostMsg_CloseStream,
                      int /* stream_id */)
 
-// Get audio volume of the stream specified by stream_id.
-IPC_MESSAGE_CONTROL1(AudioHostMsg_GetVolume,
-                     int /* stream_id */)
-
 // Get audio volume of the input stream specified by
 // (render_view_id, stream_id).
 IPC_MESSAGE_CONTROL1(AudioInputHostMsg_GetVolume,
                      int /* stream_id */)
 
 // Set audio volume of the stream specified by stream_id.
 // TODO(hclam): change this to vector if we have channel numbers other than 2.
 IPC_MESSAGE_CONTROL2(AudioHostMsg_SetVolume,
                      int /* stream_id */,
                      double /* volume */)
 
 // Set audio volume of the input stream specified by stream_id.
 IPC_MESSAGE_CONTROL2(AudioInputHostMsg_SetVolume,
                      int /* stream_id */,
                      double /* volume */)
 
 // Start the device referenced by the session_id for the input stream specified
 // by stream_id.
 IPC_MESSAGE_CONTROL2(AudioInputHostMsg_StartDevice,
                      int /* stream_id */,
                      int /* session_id */)