I adjusted the size of the matrix filtered circle in both SaveLayer
Matrix filter test variants (post-filter and backdrop filter) to move
the transformed circle outside the coverage area that would be computed
if subpass filters aren't being accounted for. Further, we need to avoid
intersecting with the pass coverage hint when the transformation being
applied by the paint's filter graph causes the Entity's space basis to
deviate from the parent pass basis. We're still able to apply it for
simple translations, though.