Revert of Fix bug in plot locking system (patchset #3 id:80001 of https://codereview...

Revert of Fix bug in plot locking system (patchset #3 id:80001 of https://codereview.chromium.org/640323002/)

Reason for revert:
Failing unit tests

Original issue's description:
> Fix bug in plot locking system
>
> In the new MultiPictureDraw tests a single hoisted layer is reused multiple times. The previous plot locking scheme allowed GrCachedLayer objects to be aggressively deleted prematurely leaving the reusing GrHoistedLayer objects with dangling pointers.
>
> This CL changes the plot locking system to add a pseudo-ref for each GrHoistedLayer.
>
> NOTRY=true
>
> Committed: https://skia.googlesource.com/skia/+/5c481666c9678f43e039ad605457be3854cf8de3

TBR=jvanverth@google.com
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/643673004