Add UMA metrics for VideoCodec.MP4 and VideoCodec.WebM

media/filters/ffmpeg_glue.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.
 
 // FFmpegGlue is an interface between FFmpeg and Chrome used to proxy FFmpeg's
 // read and seek requests to Chrome's internal data structures.  The glue works
 // through the AVIO interface provided by FFmpeg.
 //
 // AVIO works through a special AVIOContext created through avio_alloc_context()
 // which is attached to the AVFormatContext used for demuxing.  The AVIO context
@@ skipping 12 matching lines @@
 // a lock manager, and finally registering all demuxers and codecs.
 
 #ifndef MEDIA_FILTERS_FFMPEG_GLUE_H_
 #define MEDIA_FILTERS_FFMPEG_GLUE_H_
 
 #include <stdint.h>
 
 #include <memory>
 
 #include "base/macros.h"
+#include "media/base/container_names.h"
 #include "media/base/media_export.h"
 #include "media/ffmpeg/ffmpeg_deleters.h"
 
 struct AVFormatContext;
 struct AVIOContext;
 
 namespace media {
 
 class MEDIA_EXPORT FFmpegURLProtocol {
  public:
@@ skipping 21 matching lines @@
   static void InitializeFFmpeg();
 
   // See file documentation for usage.  |protocol| must outlive FFmpegGlue.
   explicit FFmpegGlue(FFmpegURLProtocol* protocol);
   ~FFmpegGlue();
 
   // Opens an AVFormatContext specially prepared to process reads and seeks
   // through the FFmpegURLProtocol provided during construction.
   bool OpenContext();
   AVFormatContext* format_context() { return format_context_; }
+  // Returns the container name. Note that it is only available after

[DaleCurtis, 2017/04/27 22:10:49]

Line break. DCHECK(open_called_); ?

[kqyang, 2017/04/27 23:10:38]

Done.

+  // calling OpenContext.
+  container_names::MediaContainerName container() const { return container_; }
 
  private:
-  bool open_called_;
-  AVFormatContext* format_context_;
+  bool open_called_ = false;
+  AVFormatContext* format_context_ = nullptr;
   std::unique_ptr<AVIOContext, ScopedPtrAVFree> avio_context_;
+  container_names::MediaContainerName container_ =
+      container_names::CONTAINER_UNKNOWN;
 
   DISALLOW_COPY_AND_ASSIGN(FFmpegGlue);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_FFMPEG_GLUE_H_