Set mSnapTrigger to false on ACTION_DOWN to prevent snapping if the user touches the bar before scrolling finished

Change-Id: I4ef2d7c3586c897de510de21008b844161955ea4
Merge "Set mSnapTrigger to false on ACTION_DOWN to prevent snapping if the user touches the bar before scrolling finished" into jellybean-mr1
Merge commit '643fbb65580670f2b874e2780ed6ec766c8885d6' into jellybean-mr1

Conflicts:
	packages/SystemUI/src/com/android/systemui/statusbar/AppSidebar.java