Fix backwards WebRTC-in-Chromium override and expose Chromium logging setup

third_party/webrtc_overrides/webrtc/base/diagnostic_logging.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef THIRD_PARTY_WEBRTC_OVERRIDES_WEBRTC_BASE_DIAGNOSTIC_LOGGING_H_
 #define THIRD_PARTY_WEBRTC_OVERRIDES_WEBRTC_BASE_DIAGNOSTIC_LOGGING_H_
 
 #include <sstream>
 #include <string>
 
@@ skipping 31 matching lines @@
 // Note that the non-standard LoggingSeverity aliases exist because they are
 // still in broad use.  The meanings of the levels are:
 //  LS_SENSITIVE: Information which should only be logged with the consent
 //   of the user, due to privacy concerns.
 //  LS_VERBOSE: This level is for data which we do not want to appear in the
 //   normal debug log, but should appear in diagnostic logs.
 //  LS_INFO: Chatty level used in debugging for all sorts of things, the default
 //   in debug builds.
 //  LS_WARNING: Something that may warrant investigation.
 //  LS_ERROR: Something that should not have occurred.
+//  LS_NONE: A level < LS_ERROR, used to disable logging.
 // Note that LoggingSeverity is mapped over to chromiums verbosity levels where
 // anything lower than or equal to the current verbosity level is written to
 // file which is the opposite of logging severity in libjingle where higher
 // severity numbers than or equal to the current severity level are written to
 // file. Also, note that the values are explicitly defined here for convenience
 // since the command line flag must be set using numerical values.
+//
+// LS_NONE is present so we can LogToDebug(LS_NONE) i.e. for ordinal
+// comparisons with other log levels.
+//
 // TODO(tommi): To keep things simple, we should just use the same values for
 // these constants as Chrome does.
-enum LoggingSeverity { LS_ERROR = 1,
+enum LoggingSeverity { LS_NONE = 0,
+                       LS_ERROR = 1,
                        LS_WARNING = 2,
                        LS_INFO = 3,
                        LS_VERBOSE = 4,
                        LS_SENSITIVE = 5,
                        INFO = LS_INFO,
                        WARNING = LS_WARNING,
                        LERROR = LS_ERROR };
 
 // LogErrorContext assists in interpreting the meaning of an error value.
 enum LogErrorContext {
@@ skipping 52 matching lines @@
 class LogMultilineState {
  public:
   size_t unprintable_count_[2];
   LogMultilineState() {
     unprintable_count_[0] = unprintable_count_[1] = 0;
   }
 };
 
 class LogMessage {
  public:
-  static void LogToDebug(int min_sev);
+  static void LogToDebug(LoggingSeverity min_sev);
 };
 
 // When possible, pass optional state variable to track various data across
 // multiple calls to LogMultiline.  Otherwise, pass NULL.
 void LogMultiline(LoggingSeverity level, const char* label, bool input,
                   const void* data, size_t len, bool hex_mode,
                   LogMultilineState* state);
 
 // TODO(grunell): Change name to InitDiagnosticLoggingDelegate or
 // InitDiagnosticLogging. Change also in init_webrtc.h/cc.
 // TODO(grunell): typedef the delegate function.
 void InitDiagnosticLoggingDelegateFunction(
     void (*delegate)(const std::string&));
 
 void SetExtraLoggingInit(
     void (*function)(void (*delegate)(const std::string&)));
 
 }  // namespace rtc
 
 #endif  // THIRD_PARTY_WEBRTC_OVERRIDES_WEBRTC_BASE_DIAGNOSTIC_LOGGING_H_