To M59: Add MediaError.message

media/base/media_log.h

 // Copyright (c) 2012 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 MEDIA_BASE_MEDIA_LOG_H_
 #define MEDIA_BASE_MEDIA_LOG_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 19 matching lines @@
   enum MediaLogLevel {
     MEDIALOG_ERROR,
     MEDIALOG_INFO,
     MEDIALOG_DEBUG,
   };
 
   // Convert various enums to strings.
   static std::string MediaLogLevelToString(MediaLogLevel level);
   static MediaLogEvent::Type MediaLogLevelToEventType(MediaLogLevel level);
   static std::string EventTypeToString(MediaLogEvent::Type type);
+
+  // Returns a string version of the status, unique to each PipelineStatus, and
+  // not including any ':'. This makes it suitable for usage in
+  // MediaError.message as the UA-specific-error-code.
   static std::string PipelineStatusToString(PipelineStatus status);
+
   static std::string BufferingStateToString(BufferingState state);
 
   static std::string MediaEventToLogString(const MediaLogEvent& event);
 
+  // Returns a string usable as part of a MediaError.message, for only
+  // PIPELINE_ERROR or MEDIA_ERROR_LOG_ENTRY events, with any newlines replaced
+  // with whitespace in the latter kind of events.
+  static std::string MediaEventToMessageString(const MediaLogEvent& event);
+
   MediaLog();
 
   // Add an event to this log. Overriden by inheritors to actually do something
   // with it.
   virtual void AddEvent(std::unique_ptr<MediaLogEvent> event);
 
-  // Retrieve an error message, if any.
-  virtual std::string GetLastErrorMessage();
+  // Returns a string usable as the contents of a MediaError.message.
+  // This method returns an incomplete message if it is called before the
+  // pertinent events for the error have been added to the log.
+  // Note: The base class definition only produces empty messages. See
+  // RenderMediaLog for where this method is meaningful.
+  virtual std::string GetErrorMessage();
 
   // Records the domain and registry of the current frame security origin to a
   // Rappor privacy-preserving metric. See:
   //   https://www.chromium.org/developers/design-documents/rappor
   virtual void RecordRapporWithSecurityOrigin(const std::string& metric);
 
   // Helper methods to create events and their parameters.
   std::unique_ptr<MediaLogEvent> CreateEvent(MediaLogEvent::Type type);
   std::unique_ptr<MediaLogEvent> CreateBooleanEvent(MediaLogEvent::Type type,
                                                     const std::string& property,
@@ skipping 107 matching lines @@
 #define LIMITED_MEDIA_LOG(level, media_log, count, max)                       \
   LAZY_STREAM(MEDIA_LOG(level, media_log),                                    \
               (count) < (max) && ((count)++ || true))                         \
       << (((count) == (max)) ? "(Log limit reached. Further similar entries " \
                                "may be suppressed): "                         \
                              : "")
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_MEDIA_LOG_H_