ccpr: Don't require flat interpolation

This requirement should have been removed at the time we switched to

Interpolation::kCanBeFlat.
Bug: skia:
Change-Id: I0b6d548e8a0fa691bb94d8169ba1c1c064f8f61d
Reviewed-on: https://skia-review.googlesource.com/154848
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
1 file changed