Fix issue 2285561: New AudioFlinger and audio driver API needed for A/V sync

Added getRenderPosition() API to IAudioFlinger to retreive number of audio frames
written by AudioFlinger to audio HAL and by DSP to DAC.

Added getRenderPosition() API to AudioHardwareInterface to retreive number of audio frames
written by DSP to DAC.

Exposed AudioTrack::getPosition() to AudioSink() to make it available to media player.

Removed excessive log in AudioHardwareGeneric.
diff --git a/libs/audioflinger/AudioDumpInterface.cpp b/libs/audioflinger/AudioDumpInterface.cpp
index 858e5aa..30e2bc9 100644
--- a/libs/audioflinger/AudioDumpInterface.cpp
+++ b/libs/audioflinger/AudioDumpInterface.cpp
@@ -379,6 +379,12 @@
     }
 }
 
+status_t AudioStreamOutDump::getRenderPosition(uint32_t *dspFrames)
+{
+    if (mFinalStream != 0 ) return mFinalStream->getRenderPosition(dspFrames);
+    return INVALID_OPERATION;
+}
+
 // ----------------------------------------------------------------------------
 
 AudioStreamInDump::AudioStreamInDump(AudioDumpInterface *interface,