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

webrtc/p2p/base/dtlstransportchannel.cc

Index: webrtc/p2p/base/dtlstransportchannel.cc
diff --git a/webrtc/p2p/base/dtlstransportchannel.cc b/webrtc/p2p/base/dtlstransportchannel.cc
index bf1dc35e75cb567305c38aef2ca011d083366032..3474237269bcf0a74a347781a800599f64aab029 100644
--- a/webrtc/p2p/base/dtlstransportchannel.cc
+++ b/webrtc/p2p/base/dtlstransportchannel.cc
@@ -79,7 +79,7 @@ rtc::StreamResult StreamInterfaceChannel::Write(const void* data,
 bool StreamInterfaceChannel::OnPacketReceived(const char* data, size_t size) {
   // We force a read event here to ensure that we don't overflow our queue.
   bool ret = packets_.WriteBack(data, size, NULL);
-  CHECK(ret) << "Failed to write packet to queue.";
+  RTC_CHECK(ret) << "Failed to write packet to queue.";
   if (ret) {
     SignalEvent(this, rtc::SE_READ, 0);
   }