With recent changes, specifically PR 14515 *and* the previous patch, the `createObjectURL` helper function is now only used with the SVG back-end.
All other call-sites, throughout the code-base, are now using `URL.createObjectURL(...)` directly and it no longer seems necessary to keep exposing the helper function in the API.
Finally, the `createObjectURL` helper function is moved into the `src/display/svg.js` file to avoid unnecessarily duplicating this code on both the main- and worker-threads.