qt: fix menus can no longer have translucent background
QVLCDialog::setWindowTransientParent()
first creates a window if it is not
already created.
Depending on the platform, a QMenu
might use special attributes for its
underlying window. Some of these special attributes, such as, translucent
background requires them to be set prior to creation.
QMenu
does such adjustments in polishing stage. Calling ensurePolished()
before calling QVLCDialog::setWindowTransientParent()
satisfies that the
window is going to be what QMenu
really wants.
Request review @chub.