Revert "Don't use analytic clip FPs when drawing to stencil"

This reverts commit 4c92d4aa3ed653afdff9996b90a1139ed1dc9420.

Reason for revert: Chromecast bot failure

Original change's description:
> Don't use analytic clip FPs when drawing to stencil
> 
> It doesn't make sense to multiply by coverage when drawing to stencil.
> This could theoretically work with FPs that discard and/or modify
> the sample mask, but for the time being an analytic FP means one that
> calculates a coverage value.
> 
> Bug: skia:7190
> Change-Id: Ic40cf6c19c377cba80bad458993582f5cc07022a
> Reviewed-on: https://skia-review.googlesource.com/67423
> Reviewed-by: Brian Salomon <bsalomon@google.com>
> Commit-Queue: Chris Dalton <csmartdalton@google.com>

TBR=bsalomon@google.com,robertphillips@google.com,csmartdalton@google.com

Change-Id: Ie5bd4852c201e47daee0920f5644141bee2d8a46
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:7190
Reviewed-on: https://skia-review.googlesource.com/68400
Reviewed-by: Chris Dalton <csmartdalton@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
13 files changed