Revert of Oilpan: fix build after r201994.

Revert of Oilpan: fix build after r201994. (patchset #1 id:1 of https://codereview.chromium.org/1327193002/ )

Reason for revert:
The patch which this patch patched caused leaks on WebKit Linux Leaks (https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Linux%20Leak/builds/14049). Reverting this patch so I can revert the other one.

Original issue's description:
> Oilpan: fix build after r201994.
> 
> TBR=oilpan-reviews
> BUG=488628
> NOTRY=true
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=202004

TBR=oilpan-reviews@chromium.org,sigbjornf@opera.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=488628
Committed: https://crrev.com/75497d81015f8a0ea597fa04a13e6d9eba8f56bd
git-svn-id: svn://svn.chromium.org/blink/trunk@202041 bbb929c8-8fbe-4397-9dbb-9b2b20218538

[Mike West, 2015-09-10 09:00:18]

Created Revert of Oilpan: fix build after r201994.

[commit-bot: I haz the power, 2015-09-10 09:00:28]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1331833002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1331833002/1

[commit-bot: I haz the power, 2015-09-10 09:00:55]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=202041

[haraken, 2015-09-10 09:02:42]

LGTM

[commit-bot: I haz the power, 2015-09-23 12:08:55]

Patchset 1 (id:??) landed as
https://crrev.com/75497d81015f8a0ea597fa04a13e6d9eba8f56bd