modify test due to behavior change

To fix the gesture conflict between magnification and TouchExplorer,
PanningScaling state is transisted when user use two fingers to swipe
and the movement of any finger is over the touchslope.

we adjust the effective panning distance by Subtracting the touchslope

Bug: 159508732
Test: atest MagnificationGestureHandlerTest
Change-Id: I3064b35b9f74a38327cc93f0e76d9ea186c454fe
1 file changed