Bug 940257 - Uplift bug 934420 and part of bug 937185. r=kats, a=koi+
Bug 940257 - Detect a stale display port in NotifyLayersUpdated and request a content repaint when that happens. r=kats, a=koi+
Bug 939962 = Set pref to enable willReadFrequently software canvas option. r=snorp, a=koi+