Use audio_session_t consistently

Bug: 27562099
Change-Id: I328d8226191386b163f2ace41233607294c50dcd
diff --git a/services/audiopolicy/AudioPolicyInterface.h b/services/audiopolicy/AudioPolicyInterface.h
index 1c41ce1..b1347f4 100644
--- a/services/audiopolicy/AudioPolicyInterface.h
+++ b/services/audiopolicy/AudioPolicyInterface.h
@@ -312,7 +312,7 @@
     virtual status_t setVoiceVolume(float volume, int delayMs = 0) = 0;
 
     // move effect to the specified output
-    virtual status_t moveEffects(int session,
+    virtual status_t moveEffects(audio_session_t session,
                                      audio_io_handle_t srcOutput,
                                      audio_io_handle_t dstOutput) = 0;