Revert of Fix Assert for gpu ConicalTwoPointGradient edgecase to be correct bounds...

Revert of Fix Assert for gpu ConicalTwoPointGradient edgecase to be correct bounds. (https://codereview.chromium.org/311373003/)

Reason for revert:
changed assert is failing

Original issue's description:
> Fix Assert for gpu ConicalTwoPointGradient edgecase to be correct bounds.
>
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/be4fd4f7349b97a7c34a4177ec26d8aea9616628

R=bsalomon@google.com
TBR=bsalomon@google.com
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Author: egdaniel@google.com

Review URL: https://codereview.chromium.org/320573002