Revert of Parallel cache - preliminary  (patchset #24 id:460001 of https://codereview.chromium.org/1264103003/ )

Reason for revert:
Breaks DrMemory in the chrome roll.

Original issue's description:
> Parallel cache.
>
> TBR=reed@google.com
>
> BUG=skia:1330,528560
>
> Committed: https://skia.googlesource.com/skia/+/6f2a486040cb25465990196c229feb47e668e87f
>
> Committed: https://skia.googlesource.com/skia/+/bf2988833e5a36c6b430da6fdd2cfebd0015adec
>
> Committed: https://skia.googlesource.com/skia/+/014ffdb01ea5317614a1569efc30c50f06434222

TBR=reed@google.com,mtklein@google.com,mtklein@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:1330,528560

Review URL: https://codereview.chromium.org/1345903002
9 files changed