Bug 944938 - Add event structs and APZ event handling for pan gesture events that can be used for  Mac touchpad scrolling. r=kats
Bug 944938 - Add a 10.6 compatibility wrapper for event phases. r=smichaud
Bug 944938 - Add a 10.6 compatibility wrapper for hasPreciseScrollingDeltas and scrollingDeltaX/Y. r=smichaud
Bug 944938 - Pass scroll events to the APZC tree manager on the async event thread. r=smichaud
Bug 944938 - Install the event tap only for wheel events. r=smichaud