Revert "Add SkCharacterization creation helper to GrContextThreadSafeProxy"

This reverts commit d76e56d93c27856b10d6636882a5ffcd79a9d967.

Reason for revert: broke NexusPlayer Vulkan

Original change's description:
> Add SkCharacterization creation helper to GrContextThreadSafeProxy
> 
> Change-Id: I8ad7cf335f2b586cf501eaa70573690fbbd53efa
> Reviewed-on: https://skia-review.googlesource.com/106105
> Reviewed-by: Brian Salomon <bsalomon@google.com>
> Commit-Queue: Robert Phillips <robertphillips@google.com>

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

Change-Id: I72b75ff700d39839f7207955566e48bb544aaf6b
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/106968
Reviewed-by: Cary Clark <caryclark@google.com>
Commit-Queue: Cary Clark <caryclark@google.com>
18 files changed