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

talk/app/webrtc/objc/RTCFileLogger.mm

 /*
  * libjingle
  * Copyright 2015 Google Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  *  1. Redistributions of source code must retain the above copyright notice,
  *     this list of conditions and the following disclaimer.
  *  2. Redistributions in binary form must reproduce the above copyright notice,
@@ skipping 91 matching lines @@
   rtc::LogMessage::LogThreads(true);
   rtc::LogMessage::LogTimestamps(true);
   rtc::LogMessage::AddLogToStream(_logSink.get(), [self rtcSeverity]);
   _hasStarted = YES;
 }
 
 - (void)stop {
   if (!_hasStarted) {
     return;
   }
-  DCHECK(_logSink);
+  RTC_DCHECK(_logSink);
   rtc::LogMessage::RemoveLogToStream(_logSink.get());
   _hasStarted = NO;
   _logSink.reset();
 }
 
 - (NSData *)logData {
   if (_hasStarted) {
     return nil;
   }
   NSMutableData* logData = [NSMutableData data];
@@ skipping 25 matching lines @@
     case kRTCFileLoggerSeverityInfo:
       return rtc::LS_INFO;
     case kRTCFileLoggerSeverityWarning:
       return rtc::LS_WARNING;
     case kRTCFileLoggerSeverityError:
       return rtc::LS_ERROR;
   }
 }
 
 @end