Revert of Turn on NVPR 4x MSAA by default when supported in DM and nanobench. (patchset #2 id:20001 of https://codereview.chromium.org/704563003/)

Reason for revert:
Timing out on nvpr when drawing conics. Fix will take some thought so reverting for now.

Original issue's description:
> Turn on NVPR 4x MSAA by default when supported in DM and nanobench.
>
> This brings DM and nanobench's default configs in line with GM's.
>
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/31f88675718966bbb7f09718b40de10c7e214739

TBR=bsalomon@google.com,mtklein@google.com,mtklein@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review URL: https://codereview.chromium.org/693933004
Add mock context and use in ResourceCacheTest.

BUG=skia:2889

Committed: https://skia.googlesource.com/skia/+/820dd6c335411aad889c1d7e8a857642ecd87e30

Review URL: https://codereview.chromium.org/702083003