Revert "Remove most of GrConfig.h"

This reverts commit 80e334dad832d1f29dfa361f1fbc113378466634.

Reason for revert: Chrome is including our private headers which means this breaks the Chrome roll:
https://chromium-review.googlesource.com/c/chromium/src/+/1953757

Original change's description:
> Remove most of GrConfig.h
> 
> Change-Id: I0f693bed0778151f93d07cd42c6b597566695ab1
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/257999
> Reviewed-by: Greg Daniel <egdaniel@google.com>
> Commit-Queue: Brian Salomon <bsalomon@google.com>

TBR=egdaniel@google.com,bsalomon@google.com

Change-Id: Ie206db9865a7f9a7e334eb248de8cff38dd31d15
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/258356
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
76 files changed