The color dialog implementation lazily initializes the widget hierarchy,
so that they are not created if we're using a native dialog. But unlike
QFileDialog, which does the same, QColorDialog failed to handle the case
where the native helper could not show a native dialog.
We now correctly lazy initialize the widget hierarchy if the native
show fails.
The WA_DontShowOnScreen state management has been left out, as it
needs some general refactoring. This patch doesn't fix, or regress,
any logic related to WA_DontShowOnScreen.
Task-number: QTBUG-108153
Change-Id: Icbd506617a2fe302bb61aab977e7c8ea4bd64878
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
b2de858a8c