Moving fail safe animation cancel to power key-up case.

CLs [1] introduces new recents animation cancelling mechanism with screenshot
previous task during task stack order change for supporting Quickstep LiveTile.

We don't want the normal animation canceling flow be disturbed by fail safe
animation canceling that makes the task bring to top unexpectedly.

Remove trigger flow when home key down & moving fail safe animation cancel
that only called when power key up without long pressing case.

[1]: I83504d578a17856623a53c04a7d3c54e5bcab5f4

Bug: 122593881
Test: manual, enabled LiveTile in Launcher dev options, swipe up to recents,
verify the task will bring to top only when power key-up.

Change-Id: I09e5daa293efcdaf46a4e3d11729898e1f5efde2