Plumb audio focus support for spitzer clients.

content/renderer/media/audio_renderer_mixer_manager.cc

Index: content/renderer/media/audio_renderer_mixer_manager.cc
diff --git a/content/renderer/media/audio_renderer_mixer_manager.cc b/content/renderer/media/audio_renderer_mixer_manager.cc
index 97d0e153fc7e9e63aafdec3c5e2576de677504d4..2e52d02df2a11fbc1159023a9d184c26b1eb53c2 100644
--- a/content/renderer/media/audio_renderer_mixer_manager.cc
+++ b/content/renderer/media/audio_renderer_mixer_manager.cc
@@ -49,9 +49,6 @@ media::AudioRendererMixer* AudioRendererMixerManager::GetMixer(
     const std::string& device_id,
     const url::Origin& security_origin,
     media::OutputDeviceStatus* device_status) {
-  // Effects are not passed through to output creation, so ensure none are set.
-  DCHECK_EQ(params.effects(), media::AudioParameters::NO_EFFECTS);
-
   const MixerKey key(source_render_frame_id, params, device_id,
                      security_origin);
   base::AutoLock auto_lock(mixers_lock_);
@@ -108,6 +105,9 @@ media::AudioRendererMixer* AudioRendererMixerManager::GetMixer(
       media::AudioParameters::AUDIO_PCM_LOW_LATENCY, params.channel_layout(),
       sample_rate, 16, buffer_size);
 
+  // Pass through any effects requests to the output device.
+  output_params.set_effects(params.effects());
+
   // If we've created invalid output parameters, simply pass on the input
   // params and let the browser side handle automatic fallback.
   if (!output_params.IsValid())