Update audio code to use size_t more correctly,

webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red.cc

Index: webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red.cc
diff --git a/webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red.cc b/webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red.cc
index 16ba290fc3366df0bd544beb709da4c7bf647c05..dccaf4306157a32e17e6cf240a2203c823414c66 100644
--- a/webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red.cc
+++ b/webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red.cc
@@ -41,11 +41,11 @@ size_t AudioEncoderCopyRed::MaxEncodedBytes() const {
   return 2 * speech_encoder_->MaxEncodedBytes();
 }
 
-int AudioEncoderCopyRed::Num10MsFramesInNextPacket() const {
+size_t AudioEncoderCopyRed::Num10MsFramesInNextPacket() const {
   return speech_encoder_->Num10MsFramesInNextPacket();
 }
 
-int AudioEncoderCopyRed::Max10MsFramesInAPacket() const {
+size_t AudioEncoderCopyRed::Max10MsFramesInAPacket() const {
   return speech_encoder_->Max10MsFramesInAPacket();
 }