Revert "Revert "SkRegion: more robust validation""

This reverts commit 7f4124058eda42e8379f2e979fabc339b8580348.

Original change's description:
> Revert "SkRegion: more robust validation"
> 
> This reverts commit 711450e948b9900011dc0d474f82bf7bc9913259.
> 
> Reason for revert: speculative revert to fix chrome roll.
> 
> Original change's description:
> > SkRegion: more robust validation
> > 
> > BUG=oss-fuzz:1864
> > Change-Id: I4c3d3c4c7b0717399fe16f227e032682b13ebc74
> > Reviewed-on: https://skia-review.googlesource.com/20322
> > Reviewed-by: Cary Clark <caryclark@google.com>
> > Commit-Queue: Hal Canary <halcanary@google.com>

TBR=halcanary@google.com,caryclark@google.com,reed@google.com

Change-Id: I1e5500cb83adeeda544282577ce55812e1b5d682
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: oss-fuzz:1864
Reviewed-on: https://skia-review.googlesource.com/20501
Reviewed-by: Hal Canary <halcanary@google.com>
Commit-Queue: Hal Canary <halcanary@google.com>
2 files changed