Reland "Add SkSL for-loop control flow test to dm."

This reverts commit 578f1acbe8a47178efb21df49561c365226f9d95.

Reason for revert: updated test to pass on Mac Intel 5100/6000

Original change's description:
> Revert "Add SkSL for-loop control flow test to dm."
>
> This reverts commit a0c266283a8ef230ad0436dbf885d2b616e7302b.
>
> Reason for revert: failing on Mac Intel
>
> Original change's description:
> > Add SkSL for-loop control flow test to dm.
> >
> > While loops and do-while loops remain untested in dm, as they are not
> > supported in ES2 (and therefore not available in Runtime Effects).
> >
> > Change-Id: I2f1bfccccd571cc4ced096bc18ebbb9ecc9f9b4a
> > Reviewed-on: https://skia-review.googlesource.com/c/skia/+/359556
> > Commit-Queue: John Stiles <johnstiles@google.com>
> > Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
> > Auto-Submit: John Stiles <johnstiles@google.com>
> > Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
>
> TBR=brianosman@google.com,ethannicholas@google.com,johnstiles@google.com
>
> Change-Id: I45335d16a695644eaeb8a535298c0efcc616c1ce
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/359840
> Reviewed-by: John Stiles <johnstiles@google.com>
> Commit-Queue: John Stiles <johnstiles@google.com>

TBR=brianosman@google.com,ethannicholas@google.com,johnstiles@google.com

Change-Id: I2dc6e870393708a12286658001b723f25a6aec4a
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/359856
Reviewed-by: John Stiles <johnstiles@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
5 files changed