added canUseFractForNegativeValues to standalone shader caps

Bug: skia:
Change-Id: I1097bc19b12266fe57775f6d15d731254bfffd2e
Reviewed-on: https://skia-review.googlesource.com/32186
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
Commit-Queue: Florin Malita <fmalita@chromium.org>
Reviewed-by: Florin Malita <fmalita@chromium.org>
1 file changed