[PPAPI] Pepper MediaStream API audio track implementation and example.

ppapi/thunk/ppb_audio_frame_thunk.cc

Index: ppapi/thunk/ppb_audio_frame_thunk.cc
diff --git a/ppapi/thunk/ppb_audio_frame_thunk.cc b/ppapi/thunk/ppb_audio_frame_thunk.cc
index 18cfdc4cdf7907a10ac0a0aa77ca9787152b73cc..692af87612dfcf8849a3709c91f428a903c2fde3 100644
--- a/ppapi/thunk/ppb_audio_frame_thunk.cc
+++ b/ppapi/thunk/ppb_audio_frame_thunk.cc
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// From ppb_audio_frame.idl modified Wed Jan 22 09:11:35 2014.
+// From ppb_audio_frame.idl modified Thu Jan 23 15:09:57 2014.
 
 #include "ppapi/c/pp_errors.h"
 #include "ppapi/c/ppb_audio_frame.h"
@@ -38,6 +38,14 @@ void SetTimestamp(PP_Resource frame, PP_TimeDelta timestamp) {
   enter.object()->SetTimestamp(timestamp);
 }
 
+PP_AudioFrame_SampleRate GetSampleRate(PP_Resource frame) {
+  VLOG(4) << "PPB_AudioFrame::GetSampleRate()";
+  EnterResource<PPB_AudioFrame_API> enter(frame, true);
+  if (enter.failed())
+    return PP_AUDIOFRAME_SAMPLERATE_UNKNOWN;
+  return enter.object()->GetSampleRate();
+}
+
 PP_AudioFrame_SampleSize GetSampleSize(PP_Resource frame) {
   VLOG(4) << "PPB_AudioFrame::GetSampleSize()";
   EnterResource<PPB_AudioFrame_API> enter(frame, true);
@@ -82,6 +90,7 @@ const PPB_AudioFrame_0_1 g_ppb_audioframe_thunk_0_1 = {
   &IsAudioFrame,
   &GetTimestamp,
   &SetTimestamp,
+  &GetSampleRate,
   &GetSampleSize,
   &GetNumberOfChannels,
   &GetNumberOfSamples,