Revert "[SkContexts] Prefactor SkCPU Code"

This reverts commit fd53afd27fa8c482376600eee5ba75e00ce84ee3.

Reason for revert: Broke Chrome roller

Failure Link: https://ci.chromium.org/ui/p/chromium/builders/try/android-binary-size/2918029/overview

Original change's description:
> [SkContexts] Prefactor SkCPU Code
>
> This CL prefactors (pre-refactors) the SkCPU code to make way for the new SkContext work. All of the changes remove SKCPU concepts, but the follow up CLs will add back similar concepts.
>
> Change-Id: Iec003f5b1573bee967672f5a77196f01ffb6aff3
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/1326156
> Commit-Queue: Alexis Cruz-Ayala <alexisdavidc@google.com>
> Reviewed-by: Greg Daniel <egdaniel@google.com>

No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Change-Id: I889c2ec2e8c7c047fd6b70d7fce684ae1277865f
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/1348516
Bot-Commit: rubber-stamper@appspot.gserviceaccount.com <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
39 files changed