Toolkits usually do not provide the ability to specify gradient steps,
which means VCL falls back to its algorithm, which at least with Skia
sometimes causes poor results.
Change-Id: I35dbf87e77d5ed36d8f257db877135a2a0be2ffe
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/106971
Tested-by: Jenkins
Reviewed-by: Luboš Luňák <l.lunak@collabora.com>