Implement writing mic audio input data to file for debugging purposes.

content/content_browser.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_static',
     '../crypto/crypto.gyp:crypto',
     '../device/battery/battery.gyp:device_battery',
     '../device/battery/battery.gyp:device_battery_mojo_bindings',
@@ skipping 1210 matching lines @@
       'browser/renderer_host/input/web_input_event_builders_android.cc',
       'browser/renderer_host/input/web_input_event_builders_android.h',
       'browser/renderer_host/input/web_input_event_builders_win.cc',
       'browser/renderer_host/input/web_input_event_builders_win.h',
       'browser/renderer_host/input/web_input_event_util.cc',
       'browser/renderer_host/input/web_input_event_util.h',
       'browser/renderer_host/input/web_input_event_util_posix.cc',
       'browser/renderer_host/input/web_input_event_util_posix.h',
       'browser/renderer_host/legacy_render_widget_host_win.cc',
       'browser/renderer_host/legacy_render_widget_host_win.h',
+      'browser/renderer_host/media/audio_input_debug_writer.cc',
+      'browser/renderer_host/media/audio_input_debug_writer.h',
       'browser/renderer_host/media/audio_input_device_manager.cc',
       'browser/renderer_host/media/audio_input_device_manager.h',
       'browser/renderer_host/media/audio_input_renderer_host.cc',
       'browser/renderer_host/media/audio_input_renderer_host.h',
       'browser/renderer_host/media/audio_input_sync_writer.cc',
       'browser/renderer_host/media/audio_input_sync_writer.h',
       'browser/renderer_host/media/audio_renderer_host.cc',
       'browser/renderer_host/media/audio_renderer_host.h',
       'browser/renderer_host/media/audio_sync_reader.cc',
       'browser/renderer_host/media/audio_sync_reader.h',
@@ skipping 897 matching lines @@
       'sources': [
         'browser/vr/vr_device.cc',
         'browser/vr/vr_device.h',
         'browser/vr/vr_device_manager.cc',
         'browser/vr/vr_device_manager.h',
         'browser/vr/vr_device_provider.h',
       ]
     }],
   ],
 }