Update audio code to use size_t more correctly, talk/ portion.

talk/app/webrtc/mediastreamhandler.h

Index: talk/app/webrtc/mediastreamhandler.h
diff --git a/talk/app/webrtc/mediastreamhandler.h b/talk/app/webrtc/mediastreamhandler.h
index 801648dc047bf11720c4460cc7d8f6a6824fd425..1782f26e73f5ec5b16390af76fc1cb58d256762c 100644
--- a/talk/app/webrtc/mediastreamhandler.h
+++ b/talk/app/webrtc/mediastreamhandler.h
@@ -82,7 +82,7 @@ class LocalAudioSinkAdapter : public AudioTrackSinkInterface,
               int bits_per_sample,
               int sample_rate,
               int number_of_channels,
-              int number_of_frames) override;
+              size_t number_of_frames) override;
 
   // cricket::AudioRenderer implementation.
   void SetSink(cricket::AudioRenderer::Sink* sink) override;