InputDispatcher: Do not change focus when using transferTouch

Since window focus requests are not fully synchronized between
InputDispatcher and WM, there can be adverse impacts of rapid gesture
transfers on the focused window. This is because when transferring
touch, we synthesize a pointer DOWN, and if that event id directed to a
non-focused window, Dispatcher will notify the policy that
onPointerDownOutsideFocus to get WM to change the focused window.

We want the concepts of touched windows and focused windows to be
orthogonal. To support this, change the behavior of the transferTouch
API to ensure that transfering touches don't result in changes in focus.

Bug: 324265767
Test: atest inputflinger_tests
Change-Id: I07607c6ac6c91a1a5ad4433b451aa8dfb23f42a7