The behavior of workspaces is different depending on whether
the overview is in window picker state, or app grid state.
When in window picker state, clicking on adjacent workspaces
should only activate them, without hiding the overview; and
clicking on the active workspace hides the overview. When in
app grid state, clicking on a workspace must always hide the
overview.
Pass the overview adjustment to Workspace, and leave overview
if the overview state is bigger than WINDOW_PICKER.
Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1645>
2e817d3fa8