Reland of SkTArray to move when moving. (patchset #1 id:1 of https://codereview.chrom...

Reland of SkTArray to move when moving. (patchset #1 id:1 of https://codereview.chromium.org/1677103002/ )

Reason for revert:
This was not the problem.

Original issue's description:
> Revert of SkTArray to move when moving. (patchset #3 id:40001 of https://codereview.chromium.org/1672063002/ )
>
> Reason for revert:
> This appears to have broken several things.
>
> Original issue's description:
> > SkTArray to move when moving.
> >
> > This updates SkTArray to move elements when possible, instead of always
> > copying them.
> >
> > TBR=reed
> > Agreed moving is good. This should also become private.
> >
> > Committed: https://skia.googlesource.com/skia/+/3c69348e725131150e4ab962dec1b3ff1148a6bd
>
> TBR=reed@google.com,mtklein@google.com,bungeman@google.com
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
>
> Committed: https://skia.googlesource.com/skia/+/2f8c9bf96ceea9d13fb0fc29285ecaf1673f2e8b

TBR=reed@google.com,mtklein@google.com,bungeman@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/1678923002