Ignore Metadata entries with incorrectly encoded characters, when setting the viewer title (bug 1605526)
Ignore Metadata entries with incorrectly encoded characters, when setting the viewer title (bug 1605526)

Apparently Ghostscript can, in some cases, generate/include `Metadata` with incorrectly encoded characters.[1] This results in the viewer title looking wrong, which we thus attempt to avoid by falling back to the `Info` entry instead.

*Please note:* Obviously it would be better if this was fixed in the `Metadata` parser instead, rather than using a viewer work-around, but I'm just not sure how or even *if* that could actually be done given that the `Metadata` stream contains no trace of the *original* character.

Fixes https://bugzilla.mozilla.org/show_bug.cgi?id=1605526

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[1] The problematic characters are from the Specials Unicode block, see https://en.wikipedia.org/wiki/Specials_(Unicode_block)

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