Fix crash when storing working sets area split-view config
When storing working sets commit 89594aed introduced a crash, which happens
when the code tries to find the parent splitter while the view doesn't have
an initialized widget. In this case calling view->widget()
method tries
to create a new widget, but fails with an assert in EditorViewWatcher::viewCreated
because no parent for the widget is given.
BUG: 441058