Move ChannelLayout into media namespace.

content/test/webrtc_audio_device_test.cc

Index: content/test/webrtc_audio_device_test.cc
diff --git a/content/test/webrtc_audio_device_test.cc b/content/test/webrtc_audio_device_test.cc
index 777f7d437a75f5d242be953f310fac9bb920cbe1..685f81d4d0d5148bd1a5d20e604bf1326cc0f68f 100644
--- a/content/test/webrtc_audio_device_test.cc
+++ b/content/test/webrtc_audio_device_test.cc
@@ -274,11 +274,11 @@ void WebRTCAudioDeviceTest::OnGetHardwareInputSampleRate(int* sample_rate) {
 }
 
 void WebRTCAudioDeviceTest::OnGetHardwareInputChannelLayout(
-    ChannelLayout* layout) {
+    media::ChannelLayout* layout) {
   EXPECT_TRUE(audio_util_callback_);
-  *layout = audio_util_callback_ ?
+  *layout = !audio_util_callback_ ? media::CHANNEL_LAYOUT_NONE :
       audio_util_callback_->GetAudioInputHardwareChannelLayout(
-          media::AudioManagerBase::kDefaultDeviceId) : CHANNEL_LAYOUT_NONE;
+          media::AudioManagerBase::kDefaultDeviceId);
 }
 
 // IPC::Listener implementation.