+++ This bug was initially created as a clone of Bug #1377586 +++ Changes since last update: #8592 Only mask char codes of (3, 0) cmap tables in the range of 0xF000 to 0… #8594 Change `var` to `let`, and use object destructuring, in a couple of previously class converted `web/*.js` files #8580 Fix how we detect and handle missing glyph data. #8596 Fixes wrong structure of fullReader.read() result. #8615 Fix a stupid spelling error in the `ASCII85Decode` name in `Parser.makeInlineImage` (issue 8613) #8555 Don't allow setting various properties, such as `currentPageNumber`/`currentScale`/`currentScaleValue`/`pagesRotation`, before `{PDFViewer, PDFThumbnailViewer}.setDocument` has been called #8621 Bump minimum eslint version to 3.19.0

Pushed by ryanvm@gmail.com: https://hg.mozilla.org/integration/mozilla-inbound/rev/940fead960ed Update pdf.js to version 1.8.522. r=bdahl