mozilla/pdf.js — pull request #4803 by mzgol (2014-05-15 15:33:19+00:00)
Title: Remove obsolete compatibility workarounds

`Object.create` & `Object.defineProperty` issues concern IE<9 and really old WebKit versions. `Object.keys` is universally available outside of oldIE as well, including Android 2.3. Firefox has unprefixed `requestAnimationFrame` long ago and the fallback to using a custom function is only slower but works.