Revert of Make SkSmallAllocator obey the RAII invariants and be expandable (patchset #6 id:100001 of https://codereview.chromium.org/2488523003/ )

Reason for revert:
Crashing Mac Perf and Test bots.

This is a flaky but extremely likely crash.  I've only seen one Mac Perf or Test bot that had this patch that didn't crash.

This should be easy to reproduce like this:
  $ gn gen out --args=is_debug=false
  $ ninja -C out dm
  $ out/dm -m xfermodes3 --config gpu

This is crashing every time I run it on my laptop, and never when I revert this CL.

Building in release and running --config gpu probably don't matter.

Original issue's description:
> Make SkSmallAllocator obey the RAII invariants and move to heap structures when needed.
>
> The biggest change is to the API which allowed code to bypass the
> destruction invariants. This destruction bypass feature was needed in
> only one use, and is totally encapsulated using createWithIniterT.
>
> BUG=skia:
> GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2488523003
>
> Committed: https://skia.googlesource.com/skia/+/d5dc657b8c3ac916f98005dafdedafe02f023449

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

Review-Url: https://codereview.chromium.org/2485853005
7 files changed