Oilpan: fix build after r177984.
Oilpan: fix build after r177984.

TBR=tkent@chromium.org,oilpan-reviews@chromium.org
BUG=388961
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/385343002

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@177994 bbb929c8-8fbe-4397-9dbb-9b2b20218538

axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk