Revert of Make LayoutImageResource::image() parameter explicit (patchset #2 id:20001 of https://codereview.chromium.org/1411693006/ )

Reason for revert:
Seems to have caused 553045

Original issue's description:
> Make LayoutImageResource::image() parameter explicit
>
> It makes the code more explicit and easier to read. No functional
> change expected.
>
> BUG=551419
>
> Committed: https://crrev.com/3059b983258e55aeacef6e0b04bdd35a72436d3b
> Cr-Commit-Position: refs/heads/master@{#358287}

TBR=fs@opera.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=551419

Review URL: https://codereview.chromium.org/1431973002

Cr-Commit-Position: refs/heads/master@{#358551}
7 files changed