Revert of Pass initDataType instead of contentType on OnNeedKey().

media/formats/mp4/mp4_stream_parser.cc

 // Copyright 2014 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.
 
 #include "media/formats/mp4/mp4_stream_parser.h"
 
 #include "base/callback.h"
 #include "base/callback_helpers.h"
 #include "base/logging.h"
 #include "base/time/time.h"
 #include "media/base/audio_decoder_config.h"
 #include "media/base/stream_parser_buffer.h"
 #include "media/base/text_track_config.h"
 #include "media/base/video_decoder_config.h"
 #include "media/base/video_util.h"
 #include "media/formats/mp4/box_definitions.h"
 #include "media/formats/mp4/box_reader.h"
 #include "media/formats/mp4/es_descriptor.h"
 #include "media/formats/mp4/rcheck.h"
 #include "media/formats/mpeg/adts_constants.h"
 
 namespace media {
 namespace mp4 {
 
-static const char kCencInitDataType[] = "cenc";
+// TODO(xhwang): Figure out the init data type appropriately once it's spec'ed.
+static const char kMp4InitDataType[] = "video/mp4";
 
 MP4StreamParser::MP4StreamParser(const std::set<int>& audio_object_types,
                                  bool has_sbr)
     : state_(kWaitingForInit),
       moof_head_(0),
       mdat_tail_(0),
       highest_end_offset_(0),
       has_audio_(false),
       has_video_(false),
       audio_track_id_(0),
@@ skipping 310 matching lines @@
   for (size_t i = 0; i < headers.size(); i++)
     total_size += headers[i].raw_box.size();
 
   std::vector<uint8> init_data(total_size);
   size_t pos = 0;
   for (size_t i = 0; i < headers.size(); i++) {
     memcpy(&init_data[pos], &headers[i].raw_box[0],
            headers[i].raw_box.size());
     pos += headers[i].raw_box.size();
   }
-  need_key_cb_.Run(kCencInitDataType, init_data);
+  need_key_cb_.Run(kMp4InitDataType, init_data);
 }
 
 bool MP4StreamParser::PrepareAVCBuffer(
     const AVCDecoderConfigurationRecord& avc_config,
     std::vector<uint8>* frame_buf,
     std::vector<SubsampleEntry>* subsamples) const {
   // Convert the AVC NALU length fields to Annex B headers, as expected by
   // decoding libraries. Since this may enlarge the size of the buffer, we also
   // update the clear byte count for each subsample if encryption is used to
   // account for the difference in size between the length prefix and Annex B
@@ skipping 258 matching lines @@
       runs.AdvanceSample();
     }
     runs.AdvanceRun();
   }
 
   return true;
 }
 
 }  // namespace mp4
 }  // namespace media