Enable platform echo cancellation through the AudioRecord path.

content/renderer/renderer_webkitplatformsupport_impl.cc

Index: content/renderer/renderer_webkitplatformsupport_impl.cc
diff --git a/content/renderer/renderer_webkitplatformsupport_impl.cc b/content/renderer/renderer_webkitplatformsupport_impl.cc
index 79cc75acd6a9d7a0a6189ad4b17f7a715e4e30bd..6013a05d052d7a7a0c20ba3c3e25d374cf3223bf 100644
--- a/content/renderer/renderer_webkitplatformsupport_impl.cc
+++ b/content/renderer/renderer_webkitplatformsupport_impl.cc
@@ -726,7 +726,8 @@ RendererWebKitPlatformSupportImpl::createAudioDevice(
   media::AudioParameters params(
       media::AudioParameters::AUDIO_PCM_LOW_LATENCY,
       layout, input_channels,
-      static_cast<int>(sample_rate), 16, buffer_size);
+      static_cast<int>(sample_rate), 16, buffer_size,
+      media::AudioParameters::NO_EFFECTS);
 
   return new RendererWebAudioDeviceImpl(params, callback, session_id);
 }