Rename setStreamOutput to invalidateStream

And simplify by removing the unused I/O handle parameter 'output'.

Change-Id: Ie9c4df17a7378066312d4ed8790fda7a9125c95e
diff --git a/include/media/IAudioFlinger.h b/include/media/IAudioFlinger.h
index 7f53bfc..7c5f33a 100644
--- a/include/media/IAudioFlinger.h
+++ b/include/media/IAudioFlinger.h
@@ -169,7 +169,7 @@
                                         audio_channel_mask_t *pChannelMask) = 0;
     virtual status_t closeInput(audio_io_handle_t input) = 0;
 
-    virtual status_t setStreamOutput(audio_stream_type_t stream, audio_io_handle_t output) = 0;
+    virtual status_t invalidateStream(audio_stream_type_t stream) = 0;
 
     virtual status_t setVoiceVolume(float volume) = 0;