Qt sends a ShortcutOverride to the focus widget to evaluate whether the
widget's key event handling has higher priority than shortcut handling.
A KeyPress is then sent if the ShortcutOverride comes back accepted, or
if the Shortcut event returns ignored.
QComboBox needs to accept the ShortcutOverride for Cancel, so that
hiding the popup has priority over application shortcuts. But it should
only hide the popup when the KeyPress event actually arrives, as
otherwise the the focus widget changes (from popup to combobox), which
breaks event delivery on macOS.
Fixes: QTBUG-108908
Pick-to: 6.4 6.4.2
Change-Id: Ie9cce1c2041cbe0e41be301686d7c3b5683e9f10
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>