Update a ton of audio code to use size_t more correctly and in general reduce

webrtc/common_audio/vad/vad_sp.h

Index: webrtc/common_audio/vad/vad_sp.h
diff --git a/webrtc/common_audio/vad/vad_sp.h b/webrtc/common_audio/vad/vad_sp.h
index b5e62593c0f4b45e6280779f59542a6ce87ef7ed..4d2b02a1ef44af26e9d343b970a231ec9c22c0f2 100644
--- a/webrtc/common_audio/vad/vad_sp.h
+++ b/webrtc/common_audio/vad/vad_sp.h
@@ -33,7 +33,7 @@
 void WebRtcVad_Downsampling(const int16_t* signal_in,
                             int16_t* signal_out,
                             int32_t* filter_state,
-                            int in_length);
+                            size_t in_length);
 
 // Updates and returns the smoothed feature minimum. As minimum we use the
 // median of the five smallest feature values in a 100 frames long window.