Fix flicker when swiping from desktop to home

When swiping up from desktop, we need to temporarily show launcher views
when user may go to overview. Hide them again when user just swiped up for
taskbar. But not hide them user is swiping home.
Previously we were always hiding launcher views when user swiped up from
desktop and that led to home or transient taskbar.
This change ensures that we only change the visibility of launcher views
when overview ui is hidden, freeform tasks are still visible, and
gesture has ended.
Otherwise there were flickers when, after swiping home, we were hiding
launcher views and then showing them again shortly after as the freeform
tasks were now hidden.

Bug: 297562634
Test: be on desktop with some open apps
      - swipe up to go home, observe that there are no flickers from
        home screen icons, widgets or hotseat
      - swipe up for transient taskbar, observe desktop apps remain
        visible
      - swipe up to go to overview, observe the other fullscreen apps
        flow in from the side

Change-Id: I14f9f95a3a22fbca6878ecea24848f271dc951d7