Properly set this.eof in CCITTFaxStream

Fixes #5133.
Fixes #4379 (two PDFs).
Fixes https://bugzilla.mozilla.org/show_bug.cgi?id=776608 (five PDFs).
Fixes all PDFs at http://www.institute-christ-king.org/latin-mass-resources/sacred-music (over 200 PDFs!).

Easier review: https://github.com/mozilla/pdf.js/pull/5136/files?w=1