add: return ""; 
context: function getContentTypeFromHeaders(cacheEntryDescriptor){  var headers, match;  if (cacheEntryDescriptor)  {      headers = cacheEntryDescriptor.getMetaDataElement("response-head");    match = /^Content-Type:\s*(.*?)\s*(?:\;|$)/mi.exec(headers);    return match[1];  }}
meta: 10234	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/10234/0517581d44f8896c1637beeeca4edad2a6195890/pageInfo.js/buggy/suite/browser/pageInfo.js