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

webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.h

Index: webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.h
diff --git a/webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.h b/webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.h
index b1a812a113419e052ecffb5e2d2d3c5cb4bc2a53..a9d58f0bf82c2f970925d2d50042f6dc28b3eb3d 100644
--- a/webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.h
+++ b/webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.h
@@ -181,7 +181,7 @@ private:
 
     // The current sample frequency and sample size when mixing.
     Frequency _outputFrequency;
-    uint16_t _sampleSize;
+    size_t _sampleSize;
 
     // Memory pool to avoid allocating/deallocating AudioFrames
     MemoryPool<AudioFrame>* _audioFramePool;