Fix Metal row/column confusion, again.

We didn't have any tests which exercised the non-square matrix case
(because such a test requires ES3), so it was silently broken. It's
now fixed. The tests exposed a DIFFERENT Quadro P400 bug which will be
fixed separately.

Change-Id: Icf24acad5ea6f18aea3d8aa5a903e7bea41a5c23
Bug: skia:12443
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/448379
Commit-Queue: John Stiles <johnstiles@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
3 files changed