Stop using LOG macros in favor of RTC_ prefixed macros.

This CL has been generated with the following script:

for m in PLOG \
  LOG_TAG \
  LOG_GLEM \
  LOG_GLE_EX \
  LOG_GLE \
  LAST_SYSTEM_ERROR \
  LOG_ERRNO_EX \
  LOG_ERRNO \
  LOG_ERR_EX \
  LOG_ERR \
  LOG_V \
  LOG_F \
  LOG_T_F \
  LOG_E \
  LOG_T \
  LOG_CHECK_LEVEL_V \
  LOG_CHECK_LEVEL \
  LOG
do
  git grep -l $m | xargs sed -i "s,\b$m\b,RTC_$m,g"
done
git checkout rtc_base/logging.h
git cl format

Bug: webrtc:8452
Change-Id: I1a53ef3e0a5ef6e244e62b2e012b864914784600
Reviewed-on: https://webrtc-review.googlesource.com/21325
Reviewed-by: Niels Moller <nisse@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20617}
diff --git a/sdk/objc/Framework/Classes/Common/RTCFileLogger.mm b/sdk/objc/Framework/Classes/Common/RTCFileLogger.mm
index afe61a8..15461f4 100644
--- a/sdk/objc/Framework/Classes/Common/RTCFileLogger.mm
+++ b/sdk/objc/Framework/Classes/Common/RTCFileLogger.mm
@@ -101,8 +101,7 @@
       break;
   }
   if (!_logSink->Init()) {
-    LOG(LS_ERROR) << "Failed to open log files at path: "
-                  << _dirPath.UTF8String;
+    RTC_LOG(LS_ERROR) << "Failed to open log files at path: " << _dirPath.UTF8String;
     _logSink.reset();
     return;
   }
diff --git a/sdk/objc/Framework/Classes/Common/RTCLogging.mm b/sdk/objc/Framework/Classes/Common/RTCLogging.mm
index cdb6b18..ab76a1d 100644
--- a/sdk/objc/Framework/Classes/Common/RTCLogging.mm
+++ b/sdk/objc/Framework/Classes/Common/RTCLogging.mm
@@ -28,7 +28,7 @@
 void RTCLogEx(RTCLoggingSeverity severity, NSString* log_string) {
   if (log_string.length) {
     const char* utf8_string = log_string.UTF8String;
-    LOG_V(RTCGetNativeLoggingSeverity(severity)) << utf8_string;
+    RTC_LOG_V(RTCGetNativeLoggingSeverity(severity)) << utf8_string;
   }
 }
 
diff --git a/sdk/objc/Framework/Classes/Common/helpers.mm b/sdk/objc/Framework/Classes/Common/helpers.mm
index 4afa15d..4409845 100644
--- a/sdk/objc/Framework/Classes/Common/helpers.mm
+++ b/sdk/objc/Framework/Classes/Common/helpers.mm
@@ -50,7 +50,7 @@
         [NSString stringWithFormat:@"Error: %ld, %@, %@", (long)error.code,
                                    error.localizedDescription,
                                    error.localizedFailureReason];
-    LOG(LS_ERROR) << StdStringFromNSString(msg);
+    RTC_LOG(LS_ERROR) << StdStringFromNSString(msg);
     return false;
   }
   return true;
@@ -124,8 +124,8 @@
     // lowPoweredModeEnabled is only available on iOS9+.
     return [NSProcessInfo processInfo].lowPowerModeEnabled;
   }
-  LOG(LS_WARNING) << "webrtc::ios::GetLowPowerModeEnabled() is not "
-                     "supported. Requires at least iOS 9.0";
+  RTC_LOG(LS_WARNING) << "webrtc::ios::GetLowPowerModeEnabled() is not "
+                         "supported. Requires at least iOS 9.0";
   return false;
 }
 #endif