A new configure argument is introduced:
--with-gtk3-build=<absolute path to GTK3 build>
When provided, libreofficekit_selectionhandles package, libreofficekitgtk
library and gtktiledviewer executable would be built on Windows using the
GTK3 libraries in the passed directory, that must contain lib/pkgconfig
subdirectory with correct pkg-config data.
Change-Id: I6504af6eec0fc73cceb26a1ce923337abe14b5c4
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/141624
Tested-by: Jenkins
Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>