Add a virtual beamforming audio device on ChromeOS.

content/common/media/media_param_traits.cc

Index: content/common/media/media_param_traits.cc
diff --git a/content/common/media/media_param_traits.cc b/content/common/media/media_param_traits.cc
index 19c3b87975badff70e7cce7c8eeb4aa5b63b443a..5fac4880d88cb50fd81912183d995631d1c11b57 100644
--- a/content/common/media/media_param_traits.cc
+++ b/content/common/media/media_param_traits.cc
@@ -27,6 +27,7 @@ void ParamTraits<AudioParameters>::Write(Message* m,
   WriteParam(m, p.frames_per_buffer());
   WriteParam(m, p.channels());
   WriteParam(m, p.effects());
+  WriteParam(m, p.mic_positions());
 }
 
 bool ParamTraits<AudioParameters>::Read(const Message* m,
@@ -35,17 +36,20 @@ bool ParamTraits<AudioParameters>::Read(const Message* m,
   AudioParameters::Format format;
   ChannelLayout channel_layout;
   int sample_rate, bits_per_sample, frames_per_buffer, channels, effects;
+  std::string mic_positions;
 
   if (!ReadParam(m, iter, &format) || !ReadParam(m, iter, &channel_layout) ||
       !ReadParam(m, iter, &sample_rate) ||
       !ReadParam(m, iter, &bits_per_sample) ||
       !ReadParam(m, iter, &frames_per_buffer) ||
-      !ReadParam(m, iter, &channels) || !ReadParam(m, iter, &effects)) {
+      !ReadParam(m, iter, &channels) || !ReadParam(m, iter, &effects) ||
+      !ReadParam(m, iter, &mic_positions)) {
     return false;
   }
 
-  AudioParameters params(format, channel_layout, channels, sample_rate,
-                         bits_per_sample, frames_per_buffer, effects);
+  AudioParameters params(format, channels, channel_layout, sample_rate,
+                         bits_per_sample, frames_per_buffer, mic_positions,
+                         effects);
   *r = params;
   return r->IsValid();
 }