Support 3 channels for audio input.

content/renderer/media/webrtc_audio_capturer.cc

 // 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.
 
 #include "content/renderer/media/webrtc_audio_capturer.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/string_util.h"
@@ skipping 155 matching lines @@
   }
 
   media::ChannelLayout channel_layout = static_cast<media::ChannelLayout>(
       device_info_.device.input.channel_layout);
   DVLOG(1) << "Audio input hardware channel layout: " << channel_layout;
   UMA_HISTOGRAM_ENUMERATION("WebRTC.AudioInputChannelLayout",
                             channel_layout, media::CHANNEL_LAYOUT_MAX + 1);
 
   // Verify that the reported input channel configuration is supported.
   if (channel_layout != media::CHANNEL_LAYOUT_MONO &&
-      channel_layout != media::CHANNEL_LAYOUT_STEREO) {
+      channel_layout != media::CHANNEL_LAYOUT_STEREO &&
+      channel_layout != media::CHANNEL_LAYOUT_STEREO_AND_KEYBOARD_MIC) {
     DLOG(ERROR) << channel_layout
                 << " is not a supported input channel configuration.";
     return false;
   }
 
   DVLOG(1) << "Audio input hardware sample rate: "
            << device_info_.device.input.sample_rate;
   media::AudioSampleRate asr;
   if (media::ToAudioSampleRate(device_info_.device.input.sample_rate, &asr)) {
     UMA_HISTOGRAM_ENUMERATION(
@@ skipping 427 matching lines @@
   DCHECK(aec_dump_file.IsValid());
   audio_processor_->StartAecDump(aec_dump_file.Pass());
 }
 
 void WebRtcAudioCapturer::StopAecDump() {
   DCHECK(thread_checker_.CalledOnValidThread());
   audio_processor_->StopAecDump();
 }
 
 }  // namespace content