Caching AudioOutputDevice instances in mixer manager

media/base/audio_renderer_mixer_input.cc

Index: media/base/audio_renderer_mixer_input.cc
diff --git a/media/base/audio_renderer_mixer_input.cc b/media/base/audio_renderer_mixer_input.cc
index 55dbfc8404f76d012cc8550ce2e45f16f7f0bec0..061c224f23719250328ded2c07e4192aab742604 100644
--- a/media/base/audio_renderer_mixer_input.cc
+++ b/media/base/audio_renderer_mixer_input.cc
@@ -15,6 +15,7 @@ namespace media {
 AudioRendererMixerInput::AudioRendererMixerInput(
     const GetMixerCB& get_mixer_cb,
     const RemoveMixerCB& remove_mixer_cb,
+    const GetDeviceInfoCB& get_device_info_cb,
     const std::string& device_id,
     const url::Origin& security_origin)
     : started_(false),
@@ -22,6 +23,7 @@ AudioRendererMixerInput::AudioRendererMixerInput(
       volume_(1.0f),
       get_mixer_cb_(get_mixer_cb),
       remove_mixer_cb_(remove_mixer_cb),
+      get_device_info_cb_(get_device_info_cb),
       device_id_(device_id),
       security_origin_(security_origin),
       mixer_(nullptr),
@@ -112,7 +114,8 @@ bool AudioRendererMixerInput::SetVolume(double volume) {
 }
 
 OutputDeviceInfo AudioRendererMixerInput::GetOutputDeviceInfo() {
-  return mixer_ ? mixer_->GetOutputDeviceInfo() : OutputDeviceInfo();
+  return mixer_ ? mixer_->GetOutputDeviceInfo()
+                : get_device_info_cb_.Run(device_id_, security_origin_);
 }
 
 void AudioRendererMixerInput::SwitchOutputDevice(