remove legacy factory for overdrawcolorfilter

Change-Id: I19453c51bf275050d6426b82a1ad717348a3ea56
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/271136
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
3 files changed