Remove the `document.readyState` polyfill
Remove the `document.readyState` polyfill

This is only relevant for browsers that we don't intend to support with PDF.js version `2.0`.

showpad/mozilla-pdf.js,nawawi/pdf.js,macroplant/pdf.js,Snuffleupagus/pdf.js,mainegreen/pdf.js,Snuffleupagus/pdf.js,nawawi/pdf.js,xavier114fch/pdf.js,mukulmishra18/pdf.js,caremerge/pdf.js,Shoobx/pdf.js,Rob--W/pdf.js,Snuffleupagus/pdf.js,timvandermeij/pdf.js,showpad/mozilla-pdf.js,Shoobx/pdf.js,macroplant/pdf.js,mozilla/pdf.js,showpad/mozilla-pdf.js,caremerge/pdf.js,mainegreen/pdf.js,Shoobx/pdf.js,timvandermeij/pdf.js,macroplant/pdf.js,mozilla/pdf.js,mukulmishra18/pdf.js,nawawi/pdf.js,mozilla/pdf.js,xavier114fch/pdf.js,Rob--W/pdf.js,timvandermeij/pdf.js