Add support for incremental cluster parsing.

media/webm/webm_constants.h

 // Copyright (c) 2011 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_CONSTANTS_H_
 #define MEDIA_WEBM_WEBM_CONSTANTS_H_
 
 namespace media {
 
 // WebM element IDs.
@@ skipping 46 matching lines @@
 const int kWebMIdTitle = 0x7BA9;
 const int kWebMIdTrackEntry = 0xAE;
 const int kWebMIdTrackNumber = 0xD7;
 const int kWebMIdTrackType = 0x83;
 const int kWebMIdTrackUID = 0x73C5;
 const int kWebMIdTracks = 0x1654AE6B;
 const int kWebMIdVideo = 0xE0;
 const int kWebMIdVoid = 0xEC;
 const int kWebMIdWritingApp = 0x5741;
 
+const int64 kWebMUnknownSize = GG_LONGLONG(0x00FFFFFFFFFFFFFF);
+
 // Default timecode scale if the TimecodeScale element is
 // not specified in the INFO element.
 const int kWebMDefaultTimecodeScale = 1000000;
 
 // Values for TrackType element.
 const int kWebMTrackTypeVideo = 1;
 const int kWebMTrackTypeAudio = 2;
 
 }  // namespace media
 
 #endif  // MEDIA_WEBM_WEBM_CONSTANTS_H_