Fix for rounded-rect clips with filters.

Don't use the base canvas size to limit raster of complex clips, since
the top canvas size may actually be larger (e.g., a blur filter which
expands the clip bounds to accommodate filter margins). Use the top
canvas bounds instead.

BUG=skia:4879,471212
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1657333002

Review URL: https://codereview.chromium.org/1657333002
8 files changed