Bug 866232 - Allow the GeckoContentController interface to identify which layer is being operated upon. r=
Bug 866232 - Flip the default APZC gesture behaviour. r=
Bug 866232 - Move around code in APZC to more easily allow creating it on the compositor thread. r=
Switch to NPZC
Bug 866232 - Add an APZCTreeManager to encapsulate the multiple APZCs corresponding to a given layer tree. r=