Keep the original class/function names when minifying code (issue 12209)
Keep the original class/function names when minifying code (issue 12209)

While this will obviously increase the size of the output of `gulp minified`/`gulp minified-es5` *slightly*, the resulting files are still a lot smaller than the non-minified builds.

See https://github.com/terser/terser#minify-options for information about various Terser options.

mozilla/pdf.js,Shoobx/pdf.js,timvandermeij/pdf.js,Snuffleupagus/pdf.js,Snuffleupagus/pdf.js,nawawi/pdf.js,mozilla/pdf.js,macroplant/pdf.js,xavier114fch/pdf.js,Shoobx/pdf.js,macroplant/pdf.js,showpad/mozilla-pdf.js,caremerge/pdf.js,timvandermeij/pdf.js,caremerge/pdf.js,nawawi/pdf.js,showpad/mozilla-pdf.js,macroplant/pdf.js,Snuffleupagus/pdf.js,xavier114fch/pdf.js,timvandermeij/pdf.js,mozilla/pdf.js,showpad/mozilla-pdf.js,nawawi/pdf.js,Shoobx/pdf.js