Desks: Use supported display when moving task to front

When moving a background desktop task to front and the desk it belonged
to prior to being in the background has already been removed, it is
possible that the display id used to find a default desk for it was a
display that does not support desktop mode.

Instead, try to find a suitable display in this order:
1. The display the task is associated with (via its TaskInfo)
2. The display in focus
3. Any display that supports desktop
4. DEFAULT_DISPLAY

It's still possible that (4) does not support desktop, but that is left
to callsites to handle as an error.

Bug: 417944041
Flag: EXEMPT bug fix
Test: Open Gmail in CD, use adb command to remove its desk and then
moveTaskToFront

Change-Id: I0009aa1b77c12403beef38b8626ea26fec047dea