When we are moving a window with a modal dialog to a different
workspace, meta_workspace_focus_default_window() can be called
with 'not_this_one' being the focused modal dialog.
Since the ancestor of that window is also being moved, we must
not focus it as an alternative to the current window; this will
cause windows to be moved back and Metacity to get into an
inconsistent confused state.
https://bugzilla.redhat.com/show_bug.cgi?id=237158https://bugzilla.gnome.org/show_bug.cgi?id=598995
88ee4c5b30