In order to eventually get rid of SystemJS and start using native `import`s instead, we'll need to provide "complete" file identifiers since otherwise there'll be MIME type errors when attempting to use `import`.
Note that Prettier, purposely, has only limited [configuration options](https://prettier.io/docs/en/options.html). The configuration file is based on [the one in `mozilla central`](https://searchfox.org/mozilla-central/source/.prettierrc) with just a few additions (to avoid future breakage if the defaults ever changes).
Prettier is being used for a couple of reasons:
- To be consistent with `mozilla-central`, where Prettier is already in use across the tree.
- To ensure a *consistent* coding style everywhere, which is automatically enforced during linting (since Prettier is used as an ESLint plugin). This thus ends "all" formatting disussions once and for all, removing the need for review comments on most stylistic matters.
Many ESLint options are now redundant, and I've tried my best to remove all the now unnecessary options (but I may have missed some).
Note also that since Prettier considers the `printWidth` option as a guide, rather than a hard rule, this patch resorts to a small hack in the ESLint config to ensure that *comments* won't become too long.
*Please note:* This patch is generated automatically, by appending the `--fix` argument to the ESLint call used in the `gulp lint` task. It will thus require some additional clean-up, which will be done in a *separate* commit.
(On a more personal note, I'll readily admit that some of the changes Prettier makes are *extremely* ugly. However, in the name of consistency we'll probably have to live with that.)
There's a fair number of (primarily) `Array`s/`TypedArray`s whose formatting we don't want disturb, since in many cases that would lead to the code becoming much more difficult to read and/or break existing inline comments.
*Please note:* It may be a good idea to look through these cases individually, and possibly re-write some of the them (especially the `String` ones) to reduce the need for all of these ignore commands.
Sometimes we also used `@return`, but `@returns` is what the JSDoc
documentation recommends. Even though `@return` works as an alias, it's
good to use the recommended syntax and to be consistent within the
project.
By utilizing a base "class", things become significantly simpler. Unfortunately the new `BaseException` cannot be a proper ES6 class and just extend `Error`, since the SystemJS dependency doesn't seem to play well with that.
Note also that we (generally) need to keep the `name` property on the actual `...Exception` object, rather than on its prototype, since the property will otherwise be dropped during the structured cloning used with `postMessage`.
The `src/shared/util.js` file is being bundled into both the `pdf.js` and `pdf.worker.js` files, meaning that its code is by definition duplicated.
Some main-thread only utility functions have already been moved to a separate `src/display/display_utils.js` file, and this patch simply extends that concept to utility functions which are used *only* on the worker-thread.
Note in particular the `getInheritableProperty` function, which expects a `Dict` as input and thus *cannot* possibly ever be used on the main-thread.
