Improve border images
Respect CSS border-image-width.
Properly support gradients as a border-image-source.
Add a new test and mark two more as passing.
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Respect CSS border-image-width.
Properly support gradients as a border-image-source.
Only emit a border item if the border-width is non-zero
for simple borders but still emit one if the item is
an image as paint worklet that are not drawn cause servo
to hang and fail tests.
Add a new test and mark 4 more as passing.
wpt tests replace all but 3 tests from forked _mozilla_ tests. These 3 were removed from wpt repo
in commit de7719144e1c7da2ca8d6a543bec428fcfd3c30f, so we can remove all forked _mozilla_
css-paint-api tests
