Improve scrolling cache

Scrolling cache helps make short scrolls/flings smooth but will
cause stutter when long flings are made. This patch disables
scrolling cache when long flings are made.

This patch also fixes a related bug where scrolling cache will
not be enabled properly when transitioning from flinging to scrolling.

Patch Set 2: Calculate threshold based on maximum velocity (Sang Tae Park)

Credits: Pawit Pornkitprasan

Change-Id: I1fdbaad92263c9f983a32900e74eba1f0367902b
Signed-off-by: Arham Jamal <arhamjamal@gmail.com>
increase touch sensitivity

Change-Id: I77e6aeca3667808e630dc142a2e561d3ddddef80
systemui: turn off debugging

should be all of it

-VanirAOSP

Change-Id: Ia279a1be6968f67a4ad448cf51743f4c455af88a