Smooth out IME animation for automotive devices

Automotive devices may request the navigation bar to be
hidden when the IME shows up (controlled via
config_automotiveHideNavBarForKeyboard) in order to maximize
the visible screen real estate. When this happens, the IME window
should animate from the bottom of the screen to reduce the jank
that happens from the lack of synchronization between the bottom
system window and the IME window.

Bug: 163418214
Test: manual
Change-Id: I5d7b03d5c829a2679efdd06fa961d1158494e08f