Fill in mic_positions property.

chromeos/audio/audio_device.cc

Index: chromeos/audio/audio_device.cc
diff --git a/chromeos/audio/audio_device.cc b/chromeos/audio/audio_device.cc
index fd6ae45e42d878958b8a746ee7f6c90bcf6cf119..27109ed9988803a007d6992b3fbde5bbf4b8d591 100644
--- a/chromeos/audio/audio_device.cc
+++ b/chromeos/audio/audio_device.cc
@@ -123,6 +123,7 @@ AudioDevice::AudioDevice(const AudioNode& node) {
   else
     display_name = node.device_name;
   device_name = node.device_name;
+  mic_positions = node.mic_positions;
   priority = GetDevicePriority(type, node.is_input);
   active = node.active;
   plugged_time = node.plugged_time;
@@ -151,6 +152,7 @@ std::string AudioDevice::ToString() const {
   base::StringAppendF(&result,
                       "plugged_time= %s ",
                       base::Uint64ToString(plugged_time).c_str());
+  base::StringAppendF(&result, "mic_positions = %s ", mic_positions.c_str());
 
   return result;
 }