Add UMA reporting for GpuVideoDecoder::Initialize status.

media/base/pipeline_status.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_PIPELINE_STATUS_H_
 #define MEDIA_BASE_PIPELINE_STATUS_H_
 
 #include "base/callback.h"
 
+#include <string>
+
 namespace media {
 
 // Status states for pipeline.  All codes except PIPELINE_OK indicate errors.
 enum PipelineStatus {
   PIPELINE_OK,
   PIPELINE_ERROR_URL_NOT_FOUND,
   PIPELINE_ERROR_NETWORK,
   PIPELINE_ERROR_DECODE,
   PIPELINE_ERROR_DECRYPT,
   PIPELINE_ERROR_ABORT,
   PIPELINE_ERROR_INITIALIZATION_FAILED,
   PIPELINE_ERROR_REQUIRED_FILTER_MISSING,
   PIPELINE_ERROR_COULD_NOT_RENDER,
   PIPELINE_ERROR_READ,
   PIPELINE_ERROR_OPERATION_PENDING,
   PIPELINE_ERROR_INVALID_STATE,
   // Demuxer related errors.
   DEMUXER_ERROR_COULD_NOT_OPEN,
   DEMUXER_ERROR_COULD_NOT_PARSE,
   DEMUXER_ERROR_NO_SUPPORTED_STREAMS,
   // Decoder related errors.
   DECODER_ERROR_NOT_SUPPORTED,
+  PIPELINE_STATUS_MAX,  // Must be greater than all other values logged.
 };
 
 typedef base::Callback<void(PipelineStatus)> PipelineStatusCB;
 
+// Wrap & return a callback around |cb| which reports its argument to UMA under
+// the requested |name|.
+PipelineStatusCB CreateUMAReportingPipelineCB(const std::string& name,
+                                              const PipelineStatusCB& cb);
+
 // TODO(scherkus): this should be moved alongside host interface definitions.
 struct PipelineStatistics {
   PipelineStatistics()
       : audio_bytes_decoded(0),
         video_bytes_decoded(0),
         video_frames_decoded(0),
         video_frames_dropped(0) {
   }
 
   uint32 audio_bytes_decoded;  // Should be uint64?
   uint32 video_bytes_decoded;  // Should be uint64?
   uint32 video_frames_decoded;
   uint32 video_frames_dropped;
 };
 
 // Used for updating pipeline statistics.
 typedef base::Callback<void(const PipelineStatistics&)> StatisticsCB;
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_PIPELINE_STATUS_H_