Extract the existing logic to map the various possible values
for the GtkMessageDialog:buttons property [1] to the VCL
equivalent from MessageDialog::set_property to a new static helper
method BuilderBase::mapGtkToVclButtonsType, for reuse in QtBuilder
in an upcoming commit.
[1] https://docs.gtk.org/gtk3/property.MessageDialog.buttons.html
Change-Id: I7eee72cde7e162733d551dc4c19936c7b837baa5
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/181724
Tested-by: Jenkins
Reviewed-by: Michael Weghorn <m.weghorn@posteo.de>
Michael Weghorn
07fe29fb7a