Made it possible for individual windows to disable pointer gestures
while the window has focus using a private API.
Cleaned up the InputReader configuration code to enable in-place
reconfiguration of input devices without having to reopen them all.
This change makes changing the pointer speed somewhat nicer since the
pointer doesn't jump back to the origin after each change.
Change-Id: I9727419c2f4cb39e16acb4b15fd7fd84526b1239
474dcb5c3d