Remove speed requirements for multi-finger swipes

Once one of the fingers has moved more than (fingerCount * touchSlop), gesture detection will start and will not cancel no matter how slow the user moves. The reasoning behind speed requirements in one-finger swipes is to distinguish between touch exploration and gesture detection. There is no such problem here.
Bug: 172670126
Bug: 170902208
Bug:162521649
Test: atest GestureManifoldTest TouchExplorerTest AccessibilityGestureDetectorTest FrameworksServicesTests:TouchExplorerTest
Change-Id: I760036415192cd1368a06b04355b775299c29d16

Change-Id: I796d6e5476cb5dc60aa85ba33c04ad62dce88eba