Revert "Use SkArenaAlloc instead of SkSmallAllocator in the SkAutoBlitterChoose code."

This reverts commit 2b57b7f7a7fc97db57f190b5a8ebcf68e177ee2d.

Reason for revert: Android compile failing

Original change's description:
> Use SkArenaAlloc instead of SkSmallAllocator in the SkAutoBlitterChoose code.
> 
> 
> TBR=reed@google.com
> Change-Id: Iefb044bf7657fbf982f23aa91a3f4d013ce2c626
> Reviewed-on: https://skia-review.googlesource.com/7786
> Reviewed-by: Mike Klein <mtklein@chromium.org>
> Reviewed-by: Herb Derby <herb@google.com>
> Commit-Queue: Herb Derby <herb@google.com>
> 

TBR=mtklein@chromium.org,mtklein@google.com,herb@google.com,reed@google.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Change-Id: Id09c35377dddae0811d998b7d0c34c422325a5bc
Reviewed-on: https://skia-review.googlesource.com/8129
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
49 files changed