Mixing audio with different latency requirements

media/base/audio_renderer_mixer_pool.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_BASE_AUDIO_RENDERER_MIXER_POOL_H_
 #define MEDIA_BASE_AUDIO_RENDERER_MIXER_POOL_H_
 
 #include <string>
 
+#include "media/base/audio_latency.h"
 #include "media/base/output_device_info.h"
 
 namespace url {
 class Origin;
 }
 
 namespace media {
 class AudioParameters;
 class AudioRendererMixer;
 
 // Provides AudioRendererMixer instances for shared usage.
 // Thread safe.
 class MEDIA_EXPORT AudioRendererMixerPool {
  public:
   AudioRendererMixerPool() {}
   virtual ~AudioRendererMixerPool() {}
 
   // Obtains a pointer to mixer instance based on AudioParameters. The pointer
   // is guaranteed to be valid (at least) until it's rereleased by a call to
   // ReturnMixer().
   virtual AudioRendererMixer* GetMixer(int owner_id,
                                        const AudioParameters& params,
+                                       AudioLatency::LatencyType latency,
                                        const std::string& device_id,
                                        const url::Origin& security_origin,
                                        OutputDeviceStatus* device_status) = 0;
 
   // Returns mixer back to the pool, must be called when the mixer is not needed
   // any more to avoid memory leakage.
-  virtual void ReturnMixer(int owner_id,
-                           const AudioParameters& params,
-                           const std::string& device_id,
-                           const url::Origin& security_origin) = 0;
+  virtual void ReturnMixer(AudioRendererMixer* mixer) = 0;
 
   // Returns output device information
   virtual OutputDeviceInfo GetOutputDeviceInfo(
       int owner_id,
       int session_id,
       const std::string& device_id,
       const url::Origin& security_origin) = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(AudioRendererMixerPool);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_AUDIO_RENDERER_MIXER_POOL_H_