Revert of [Suggestions] Create ImageEncoder, to abstract away image encode/decode.

Revert of [Suggestions] Create ImageEncoder, to abstract away image encode/decode. (patchset #4 id:170001 of https://codereview.chromium.org/630073002/)

Reason for revert:
It is no longer needed, we decided on a different approach.

Original issue's description:
> [Suggestions] Create ImageEncoder, to abstract away image encode/decode.
>
> iOS can't depend on JPEG encoder.
>
> TBR=jam
> BUG=387751, 409156
>
> Committed: https://crrev.com/f5e2e2fa7303d699027095cd9b7cfb9462b585f6
> Cr-Commit-Position: refs/heads/master@{#298510}

TBR=huangs@chromium.org,blundell@chromium.org,jam@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=387751, 409156
Committed: https://crrev.com/60143a3967b0a687f05a166db2314f0495d1fe10
Cr-Commit-Position: refs/heads/master@{#298706}

[Mathieu, 2014-10-08 14:50:55]

Created Revert of [Suggestions] Create ImageEncoder, to abstract away image
encode/decode.

[commit-bot: I haz the power, 2014-10-08 14:51:56]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/634273002/1

[commit-bot: I haz the power, 2014-10-08 14:53:01]

Committed patchset #1 (id:1) as b5b9d576cf7bc8aae11ad5eec9de20a9a57b8fe5

[blundell, 2014-10-08 14:53:21]

LGTM

Apologies for leading you in the wrong direction :(.

[commit-bot: I haz the power, 2014-10-08 14:53:52]

Patchset 1 (id:??) landed as
https://crrev.com/60143a3967b0a687f05a166db2314f0495d1fe10
Cr-Commit-Position: refs/heads/master@{#298706}