nl_tokens: Load a TextTrack from a specifed url .
pl_tokens: function loadTrack ( src , track ) { var opts = { uri : src } ; var crossOrigin = isCrossOrigin ( src ) ; if ( crossOrigin ) { opts . cors = crossOrigin ; } xhr ( opts , bind ( this , function ( err , response , responseBody ) { if ( err ) { return log$1 . error ( err , <mask> ) ; } track . loaded_ = true ; // Make sure that vttjs has loaded, otherwise, wait till it finished loading // NOTE: this is only used for the alt/video.novtt.js build if ( typeof window . WebVTT !== 'function' ) { if ( track . tech_ ) { var loadHandler = function loadHandler ( ) { return parseCues ( responseBody , track ) ; } ; track . tech_ . on ( 'vttjsloaded' , loadHandler ) ; track . tech_ . on ( 'vttjserror' , function ( ) { log$1 . error ( 'vttjs failed to load, stopping trying to process ' + track . src ) ; track . tech_ . off ( 'vttjsloaded' , loadHandler ) ; } ) ; } } else { parseCues ( responseBody , track ) ; } } ) ) ; }