audio policy: binder calls for dynamic audio policy mixes

Add binder calls to register and unregister dynamic mixes
to AudioPolicyManager.

Bug: 16009464.

Change-Id: I4ef38166d0cfc88c984970969380d0cd6eb083ac
diff --git a/include/media/AudioSystem.h b/include/media/AudioSystem.h
index bf1fc1c..843a354 100644
--- a/include/media/AudioSystem.h
+++ b/include/media/AudioSystem.h
@@ -18,6 +18,7 @@
 #define ANDROID_AUDIOSYSTEM_H_
 
 #include <hardware/audio_effect.h>
+#include <media/AudioPolicy.h>
 #include <media/IAudioFlingerClient.h>
 #include <media/IAudioPolicyServiceClient.h>
 #include <system/audio.h>
@@ -324,6 +325,8 @@
 
     static audio_mode_t getPhoneState();
 
+    static status_t registerPolicyMixes(Vector<AudioMix> mixes, bool registration);
+
     // ----------------------------------------------------------------------------
 
     class AudioPortCallback : public RefBase