Revert "Hook up ShaderErrorHandler in the Metal backend."

This reverts commit 69df532a55b97c3f95e9322929cf11e5d9c5d5fb.

Reason for revert: See if this is causing the iOS redness on our tree

Original change's description:
> Hook up ShaderErrorHandler in the Metal backend.
>
> Also cleans up dumping of shader code to use GrShaderUtils.
>
> Change-Id: I4d2a13e1a54284d7da0242b74cebb3900921fc35
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/337077
> Commit-Queue: Jim Van Verth <jvanverth@google.com>
> Reviewed-by: Brian Osman <brianosman@google.com>

TBR=jvanverth@google.com,brianosman@google.com

Change-Id: I34125bd560cfbd12e50c732137cf921067457be2
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/337184
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
7 files changed