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 1a30a6df5eee9a30b73672504623ac642010b47f..108f327e205c6d9b23c838094725467ddff8aa17 100644
--- a/content/renderer/renderer_webkitplatformsupport_impl.cc
+++ b/content/renderer/renderer_webkitplatformsupport_impl.cc
@@ -725,7 +725,8 @@ 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);
 }