Add RTC_ prefix to (D)CHECKs and related macros.

webrtc/modules/audio_coding/neteq/dtmf_buffer.cc

Index: webrtc/modules/audio_coding/neteq/dtmf_buffer.cc
diff --git a/webrtc/modules/audio_coding/neteq/dtmf_buffer.cc b/webrtc/modules/audio_coding/neteq/dtmf_buffer.cc
index b3c02e006534e499958bee86b3d2274acdbd9a8c..779d1d340b46559169f4ab2140e6710ae36cddf2 100644
--- a/webrtc/modules/audio_coding/neteq/dtmf_buffer.cc
+++ b/webrtc/modules/audio_coding/neteq/dtmf_buffer.cc
@@ -70,8 +70,8 @@ int DtmfBuffer::ParseEvent(uint32_t rtp_timestamp,
                            const uint8_t* payload,
                            size_t payload_length_bytes,
                            DtmfEvent* event) {
-  CHECK(payload);
-  CHECK(event);
+  RTC_CHECK(payload);
+  RTC_CHECK(event);
   if (payload_length_bytes < 4) {
     LOG(LS_WARNING) << "ParseEvent payload too short";
     return kPayloadTooShort;