Support large desktop tile in grid only overview

Based on UX specs, desktop tile should be using the large size and be
pinned ot the right in overview.
Updates to ensure the desktop tile is using the focused tile size when
grid only overview is enabled.

Test: enable grid only overview, have some fullscreen tasks in overview
  and some desktop tasks, open overview from home, observe desktop tile
  peeks from right
Test: same setup as before, open a fullscreen app, open overview,
  observe desktop tile peeks in from right
Test: same setup as before, go to desktop, open overview, observe
  desktop tile is focused
Test: turn off grid only overview, repeat the same test case

Bug: 271131878

Change-Id: Ic804428dca415f08a26c47e1d6b9b3a94fcfbfdf