Backout c1e84483fc87 for Android bustage
Bug 890072 - Part 1: Factor out PlayingRefChanged from DelayNodeEngine; r=roc
Bug 890072 - Part 2: Keep the ConvolverNode alive while its reverb buffers are being exhausted; r=roc
Backed out 2 changesets (bug 890072) because gcc sucks

Backed out changeset ff011e5b3655 (bug 890072)
Backed out changeset 0ed650741dc5 (bug 890072)
Bug 888497 - Fix focus order of browser toolbar. r=sriram
Bug 879111 - Mute Web Audio when allowMedia is false on the docshell. r=ehsan
Bug 870101 - Make BackgroundPageThumbs load about:blank after capturing windows so that they're eventually collected. r=markh