Reland CL to implement browser-side logging to WebRtc log.

content/browser/renderer_host/media/media_stream_manager.h

Index: content/browser/renderer_host/media/media_stream_manager.h
diff --git a/content/browser/renderer_host/media/media_stream_manager.h b/content/browser/renderer_host/media/media_stream_manager.h
index eefab6bdcb2087ddfc4890a8f7b1c93a3691050f..88f02e1f36cdfd0a2c9cdb940826bcb1aa11ffe1 100644
--- a/content/browser/renderer_host/media/media_stream_manager.h
+++ b/content/browser/renderer_host/media/media_stream_manager.h
@@ -24,6 +24,7 @@
 #define CONTENT_BROWSER_RENDERER_HOST_MEDIA_MEDIA_STREAM_MANAGER_H_
 
 #include <map>
+#include <set>
 #include <string>
 
 #include "base/basictypes.h"
@@ -185,6 +186,15 @@ class CONTENT_EXPORT MediaStreamManager
   // too late. (see http://crbug.com/247525#c14).
   virtual void WillDestroyCurrentMessageLoop() OVERRIDE;
 
+  // Sends log messages to the render processes making device requests, to be
+  // used by the webrtcLoggingPrivate API if requested.
+  void AddLogMessageOnIOThread(const std::string& message);
+
+  // Adds |message| to native logs for outstanding device requests, for use by
+  // render processes requesting logging from webrtcLoggingPrivate API. Safe to
+  // call from any thread.
+  static void SendMessageToNativeLog(const std::string& message);
+
  protected:
   // Used for testing.
   MediaStreamManager();
@@ -310,6 +320,12 @@ class CONTENT_EXPORT MediaStreamManager
   void TranslateDeviceIdToSourceId(DeviceRequest* request,
                                    MediaStreamDevice* device);
 
+  // Helper method that sends log messages to the render processes in
+  // |render_process_ids|, to be used by the webrtcLoggingPrivate API if
+  // requested.
+  void AddLogMessageOnUIThread(const std::set<int>& render_process_ids,
+                               const std::string& message);
+
   // Finds and returns the device id corresponding to the given
   // |source_id|. Returns true if there was a raw device id that matched the
   // given |source_id|, false if nothing matched it.
@@ -339,7 +355,7 @@ class CONTENT_EXPORT MediaStreamManager
   // AudioInputDeviceManager, in order to only enumerate when necessary.
   int active_enumeration_ref_count_[NUM_MEDIA_TYPES];
 
-  // All non-closed request.
+  // All non-closed request. Must be accessed on IO thread.
   DeviceRequests requests_;
 
   // Hold a pointer to the IO loop to check we delete the device thread and