Fix errors caused by unsafe conversions to/from size_t

third_party/WebKit/Source/core/html/track/vtt/VTTParser.cpp

 /*
  * Copyright (C) 2011 Google Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 83 matching lines @@
     ASSERT(outputCues.isEmpty());
     outputCues.swap(m_cueList);
 }
 
 void VTTParser::getNewRegions(HeapVector<Member<VTTRegion>>& outputRegions)
 {
     ASSERT(outputRegions.isEmpty());
     outputRegions.swap(m_regionList);
 }
 
-void VTTParser::parseBytes(const char* data, unsigned length)
+void VTTParser::parseBytes(const char* data, size_t length)
 {
     String textData = m_decoder->decode(data, length);
     m_lineReader.append(textData);
     parse();
 }
 
 void VTTParser::flush()
 {
     String textData = m_decoder->flush();
     m_lineReader.append(textData);
@@ skipping 444 matching lines @@
 }
 
 DEFINE_TRACE(VTTParser)
 {
     visitor->trace(m_document);
     visitor->trace(m_cueList);
     visitor->trace(m_regionList);
 }
 
 }