Use std::string for decryption key ID in webm parser.

media/webm/webm_tracks_parser.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_WEBM_WEBM_TRACKS_PARSER_H_
 #define MEDIA_WEBM_WEBM_TRACKS_PARSER_H_
 
+#include <string>
+
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/time.h"
 #include "media/webm/webm_content_encodings_client.h"
 #include "media/webm/webm_parser.h"
 
 namespace media {
 
 // Parser for WebM Tracks element.
 class WebMTracksParser : public WebMParserClient {
  public:
   explicit WebMTracksParser();
   virtual ~WebMTracksParser();
 
   // Parses a WebM Tracks element in |buf|.
   //
   // Returns -1 if the parse fails.
   // Returns 0 if more data is needed.
   // Returns the number of bytes parsed on success.
   int Parse(const uint8* buf, int size);
 
   int64 audio_track_num() const { return audio_track_num_; }
   int64 video_track_num() const { return video_track_num_; }
 
-  const uint8* video_encryption_key_id() const;
-  int video_encryption_key_id_size() const;
+  const std::string& video_encryption_key_id() const;
 
  private:
   // WebMParserClient methods
   virtual WebMParserClient* OnListStart(int id) OVERRIDE;
   virtual bool OnListEnd(int id) OVERRIDE;
   virtual bool OnUInt(int id, int64 val) OVERRIDE;
   virtual bool OnFloat(int id, double val) OVERRIDE;
   virtual bool OnBinary(int id, const uint8* data, int size) OVERRIDE;
   virtual bool OnString(int id, const std::string& str) OVERRIDE;
 
   int64 track_type_;
   int64 track_num_;
   scoped_ptr<WebMContentEncodingsClient> track_content_encodings_client_;
 
   int64 audio_track_num_;
   scoped_ptr<WebMContentEncodingsClient> audio_content_encodings_client_;
 
   int64 video_track_num_;
   scoped_ptr<WebMContentEncodingsClient> video_content_encodings_client_;
 
   DISALLOW_COPY_AND_ASSIGN(WebMTracksParser);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_WEBM_WEBM_TRACKS_PARSER_H_