Add AudioTrackRecorder for audio component of MediaStream recording.

content/content_renderer.gypi

 # 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.
 
 {
   'dependencies': [
     '../base/base.gyp:base',
     '../base/third_party/dynamic_annotations/dynamic_annotations.gyp:dynamic_annotations',
     '../cc/cc.gyp:cc',
     '../cc/blink/cc_blink.gyp:cc_blink',
@@ skipping 597 matching lines @@
       'public/renderer/media_stream_audio_sink.h',
       'public/renderer/media_stream_renderer_factory.h',
       'public/renderer/media_stream_sink.h',
       'public/renderer/media_stream_video_sink.cc',
       'public/renderer/media_stream_video_sink.h',
       'public/renderer/webrtc_log_message_delegate.h',
     ],
     # WebRTC-specific sources. Put WebRTC plugin-related stuff in the
     # Plugin+WebRTC section below.
     'private_renderer_webrtc_sources': [
+      'renderer/media/audio_track_recorder.cc',
+      'renderer/media/audio_track_recorder.h',
       'renderer/media/media_recorder_handler.cc',
       'renderer/media/media_recorder_handler.h',
       'renderer/media/media_stream.cc',
       'renderer/media/media_stream.h',
       'renderer/media/media_stream_audio_processor.cc',
       'renderer/media/media_stream_audio_processor.h',
       'renderer/media/media_stream_audio_processor_options.cc',
       'renderer/media/media_stream_audio_processor_options.h',
       'renderer/media/media_stream_audio_sink_owner.cc',
       'renderer/media/media_stream_audio_sink_owner.h',
@@ skipping 152 matching lines @@
       ],
     }],
     ['OS=="win" and win_use_allocator_shim==1', {
       'dependencies': [
           '../base/allocator/allocator.gyp:allocator',
       ],
     }],
     ['OS=="android"', {
       'sources!': [
         'renderer/media/audio_decoder.cc',
+        'renderer/media/audio_track_recorder.cc',
+        'renderer/media/audio_track_recorder.h',
         'renderer/media/media_recorder_handler.cc',
         'renderer/media/media_recorder_handler.h',
         'renderer/media/video_track_recorder.cc',
         'renderer/media/video_track_recorder.h',
         'renderer/usb/type_converters.cc',
         'renderer/usb/type_converters.h',
         'renderer/usb/web_usb_client_impl.cc',
         'renderer/usb/web_usb_client_impl.h',
         'renderer/usb/web_usb_device_impl.cc',
         'renderer/usb/web_usb_device_impl.h',
@@ skipping 112 matching lines @@
     }],
   ],
   'target_conditions': [
     ['OS=="android"', {
       'sources/': [
         ['include', '^renderer/render_view_linux\\.cc$'],
       ],
     }],
   ],
 }