Revert of Add color xform support to SkWebpCodec (patchset #2 id:80001 of https://codereview.chromium.org/2294993002/ )

Reason for revert:
Windows bots hate it when I upload new images.

Original issue's description:
> Add color xform support to SkWebpCodec
>
> BUG=skia:
> GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2294993002
>
> Committed: https://skia.googlesource.com/skia/+/828ed1777da74692d0c8a5834017929f5aedcc6b

TBR=scroggo@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/2318253004
4 files changed