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/services/audiopolicy/AudioPolicyInterfaceImplLegacy.cpp b/services/audiopolicy/AudioPolicyInterfaceImplLegacy.cpp
index 4e42b25..4bc3c7f 100644
--- a/services/audiopolicy/AudioPolicyInterfaceImplLegacy.cpp
+++ b/services/audiopolicy/AudioPolicyInterfaceImplLegacy.cpp
@@ -555,7 +555,7 @@
 
 status_t AudioPolicyService::getOutputForAttr(const audio_attributes_t *attr,
                                               audio_io_handle_t *output,
-                                              audio_session_t session,
+                                              audio_session_t session __unused,
                                               audio_stream_type_t *stream,
                                               uint32_t samplingRate,
                                               audio_format_t format,
@@ -590,4 +590,10 @@
     return INVALID_OPERATION;
 }
 
+status_t AudioPolicyService::registerPolicyMixes(Vector<AudioMix> mixes __unused,
+                                                 bool registration __unused)
+{
+    return INVALID_OPERATION;
+}
+
 }; // namespace android