Clean out platform specific things from voice_engine_defines.h.

webrtc/audio/audio_send_stream.cc

Index: webrtc/audio/audio_send_stream.cc
diff --git a/webrtc/audio/audio_send_stream.cc b/webrtc/audio/audio_send_stream.cc
index 8d4ad3221ffc6f96e91440190fdd8d226976222f..ec18125427282d4624543bc45b274d2b1a42692e 100644
--- a/webrtc/audio/audio_send_stream.cc
+++ b/webrtc/audio/audio_send_stream.cc
@@ -35,7 +35,7 @@ namespace {
 constexpr char kOpusCodecName[] = "opus";
 
 bool IsCodec(const webrtc::CodecInst& codec, const char* ref_name) {
-  return (_stricmp(codec.plname, ref_name) == 0);
+  return (STR_CASE_CMP(codec.plname, ref_name) == 0);
 }
 }  // namespace