Check xlink:href for gradientUnits="userSpaceOnUse"
Created by: nthykier
When considering to prune attributes set to a default values, we
checked the gradientUnits
attribute first to determine if that was
valid. Unfortunately, we omitted to check whether the gradientUnits
attribute was inherited via xlink:ref
. This commit corrects that
bug.
Closes: #225 Signed-off-by: Niels Thykier niels@thykier.net