Bug 850424 - Clear private download notifications on last-pb-context-exited. r=mfinkle
Bug 849723 - Introduce API to use the private hidden window correctly. r=ehsan
Bug 850690 - Fix gap sometimes appearing between dynamic toolbar and page. r=kats

Backout bug 797942 as it should no longer be necessary after bug 844275 and
can cause surface size races during startup.
Bug 762902: Add a new ReflowChild flag within nsContainerState to disable deletion of next-in-flow children to prevent crash. [r=mats]