Amend d934fd7f54, which was too naive in
assuming that any change to the popup stack while a popup had been
pressed into should result in mouse move events to be delivered without
buttons.
Instead, add a new flag that is set explicitly when the qt_popup_down
widget is closed, and remove buttons from the move move events only when
that flag is set.
Add the sorely missing test case as well, even if we have to accept that
not all behavior can be tested reliably. Ie. on macOS, the simulated
mouse event differs from the event we do get from the QPA plugin or the
system; on Xcb, some of the behavior depends on the window manager.
This is something we could try to clean up for Qt 6.
Change-Id: Ibf0a0a6fb7d401915057365788947e5a35aa20c3
Fixes: QTBUG-84926
Task-number: QTBUG-82538
Pick-to: 5.15
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Liang Qi <liang.qi@qt.io>
ab6861b01f