Remove unnecessary function names in the `src/core/worker.js` file
Remove unnecessary function names in the `src/core/worker.js` file

Currently *some* functions in this file have names while others don't, and in a few cases the names are no longer entirely accurate.
For the relevant functions there should really be no need to name them, and if memory serves this was originally done since browsers (many years ago) didn't always handle anonymous functions correctly in stack traces.

showpad/mozilla-pdf.js,showpad/mozilla-pdf.js,Snuffleupagus/pdf.js,Snuffleupagus/pdf.js,Snuffleupagus/pdf.js,mozilla/pdf.js,mozilla/pdf.js,showpad/mozilla-pdf.js,mozilla/pdf.js