Add AudioSystem::getFrameCountHAL()

And add comments about declaring methods in binder opcode order.

Bug: 28117362
Change-Id: I3c4426fa4bb3ce9c4a207a44d3bb1103d7fef160
diff --git a/services/audioflinger/AudioFlinger.h b/services/audioflinger/AudioFlinger.h
index 5f4b0f1..96d38d0 100644
--- a/services/audioflinger/AudioFlinger.h
+++ b/services/audioflinger/AudioFlinger.h
@@ -131,6 +131,7 @@
     virtual     uint32_t    sampleRate(audio_io_handle_t ioHandle) const;
     virtual     audio_format_t format(audio_io_handle_t output) const;
     virtual     size_t      frameCount(audio_io_handle_t ioHandle) const;
+    virtual     size_t      frameCountHAL(audio_io_handle_t ioHandle) const;
     virtual     uint32_t    latency(audio_io_handle_t output) const;
 
     virtual     status_t    setMasterVolume(float value);