Bug 918273 - Pass back the target scrollable layer id from apzc event methods. r=kats
Bug 918273 - Cache the target scrollable layer id in metro input code and use it instead of the root layer id in ContentReceivedEvent calls. r=mbrbeck
Bug 918273 - Don't wait for the first touch move to call ContentReceivedTouch if the first touchstart had preventDefault called on it. r=mbrbeck
Bug 918273 - Add an apzc tree manager helper for translating device to gecko coordinate space, and use it when sending events to the dom in cases where content is consuming touch. r=kats