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/rtc_base/sslfingerprint.cc b/rtc_base/sslfingerprint.cc
index 3f4555b..dda46f1 100644
--- a/rtc_base/sslfingerprint.cc
+++ b/rtc_base/sslfingerprint.cc
@@ -67,14 +67,15 @@
     const RTCCertificate* cert) {
   std::string digest_alg;
   if (!cert->ssl_certificate().GetSignatureDigestAlgorithm(&digest_alg)) {
-    LOG(LS_ERROR) << "Failed to retrieve the certificate's digest algorithm";
+    RTC_LOG(LS_ERROR)
+        << "Failed to retrieve the certificate's digest algorithm";
     return nullptr;
   }
 
   SSLFingerprint* fingerprint = Create(digest_alg, cert->identity());
   if (!fingerprint) {
-    LOG(LS_ERROR) << "Failed to create identity fingerprint, alg="
-                  << digest_alg;
+    RTC_LOG(LS_ERROR) << "Failed to create identity fingerprint, alg="
+                      << digest_alg;
   }
   return fingerprint;
 }