Assign blame for playback wakelocks.

Set a work source for the playback wakelock, so that playback is
counted against the requesting app instead of the media server.

Change-Id: I7329f88a288a95a582a78005a1c3d16a5a611e31
diff --git a/services/audioflinger/AudioFlinger.h b/services/audioflinger/AudioFlinger.h
index d6b10f7..d244c14 100644
--- a/services/audioflinger/AudioFlinger.h
+++ b/services/audioflinger/AudioFlinger.h
@@ -109,6 +109,7 @@
                                 pid_t tid,
                                 int *sessionId,
                                 String8& name,
+                                int clientUid,
                                 status_t *status /*non-NULL*/);
 
     virtual sp<IAudioRecord> openRecord(