Revert of Slim Skia down to just one murmur3 implementation. (https://codereview...

Revert of Slim Skia down to just one murmur3 implementation. (https://codereview.chromium.org/376183004/)

Reason for revert:
Valgrind unhappy.  skia:2735

Original issue's description:
> Slim Skia down to just one murmur3 implementation.
>
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/6ac0037b70410ff7d5ce5788bc89314223e1a587

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

Author: mtklein@google.com

Review URL: https://codereview.chromium.org/378413002