don't draw non-finite contexts in imagefilters

Bug: skia:7507
Change-Id: Ifc210951c17f74770f15de1c2e13b42117a3354e
Reviewed-on: https://skia-review.googlesource.com/101202
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
3 files changed