Enable platform echo cancellation through the AudioRecord path.

media/audio/mac/audio_manager_mac.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 "media/audio/mac/audio_manager_mac.h"
 
 #include <CoreAudio/AudioHardware.h>
 #include <string>
 
 #include "base/bind.h"
@@ skipping 656 matching lines @@
 
     if (input_channels > 0) {
       // TODO(xians): given the limitations of the AudioOutputStream
       // back-ends used with synchronized I/O, we hard-code to stereo.
       // Specifically, this is a limitation of AudioSynchronizedStream which
       // can be removed as part of the work to consolidate these back-ends.
       channel_layout = CHANNEL_LAYOUT_STEREO;
     }
   }
 
+  if (channel_layout == CHANNEL_LAYOUT_UNSUPPORTED)
+    channel_layout = CHANNEL_LAYOUT_DISCRETE;
+  else
+    hardware_channels = ChannelLayoutToChannelCount(channel_layout);
+
   AudioParameters params(
       AudioParameters::AUDIO_PCM_LOW_LATENCY,
       channel_layout,
+      hardware_channels,
       input_channels,
       hardware_sample_rate,
       16,
-      buffer_size);
-
-  if (channel_layout == CHANNEL_LAYOUT_UNSUPPORTED)
-    params.SetDiscreteChannels(hardware_channels);
+      buffer_size,
+      AudioParameters::NO_EFFECTS);
 
   return params;
 }
 
 void AudioManagerMac::CreateDeviceListener() {
   DCHECK(GetMessageLoop()->BelongsToCurrentThread());
 
   // Get a baseline for the sample-rate and current device,
   // so we can intelligently handle device notifications only when necessary.
   current_sample_rate_ = HardwareSampleRate();
@@ skipping 44 matching lines @@
   }
 
   return buffer_size;
 }
 
 AudioManager* CreateAudioManager(AudioLogFactory* audio_log_factory) {
   return new AudioManagerMac(audio_log_factory);
 }
 
 }  // namespace media