Compare against isVisibleTo() in QLineEditIconButton::actionEvent()
so that action events received before show() are handled correctly.
Fix a regression introduced by change
4dccb2ca67 for handling action
events causing side widgets to overlap when added before the widget was
shown. Use QAction::isVisible() to determine visibility.
Task-number: QTBUG-48806
Task-number: QTBUG-48899
Task-number: QTBUG-39660
Change-Id: I7a39a3b9a094f2c74cde09544f1158deb2b81cf2
Reviewed-by: David Faure <david.faure@kdab.com>