Adapt shell transitions into legacy remote animations in systemui

systemui also defines several remote animations. Given the number
and complexity of animation entry-points in sysui, insert a
cheeky hack to swap remotetransitions in for remoteanimations
when shell transitions are enabled.

Bug: 217810915
Test: Open quick-settings, poke Settings icon. Observe animation
      and no paus.
Change-Id: I462034210f28051a03812eb6ae650fa1f0446ef5