mozilla/pdf.js — pull request #5005 by fkaelberer (2014-06-25 18:40:36+00:00)
Title: Faster chunkedStream_getByte()

Even though #4966 accelerated `ensureRange()` a lot, it is faster to avoid the check altogether. If the byte array is non-zero at the requested position, the data must have been loaded already, so we can skip `ensureByte()`.

This speeds up some PDFs considerably, for example, page 11 of the [tracemonkey](http://cdn.mozilla.net/pdfjs/tracemonkey.pdf#pdfBug=Stats&page=11&zoom=50) paper now loads 20-30% faster.