Bug 974580 - _timer shouldn't be null. r=allstars.chh, a=fabrice
Bug 969469 - Use SyncRunnable to get local interface information on gonk. r=bwc, a=fabrice
Bug 976370 - Move overlay scrollbar display items above scroll layer items for the same scroll frame. r=roc, a=fabrice

This has two desirable side effects. The first and more important is that it prevents a scrollbar item from sitting between scroll layer items and preventing them from merging into one and thus preventing the creation of an async scrollable layer. The second is that scrollbars should be on top of the content they are scrolling in general, and this will make that happen in more cases.