Fix GCC 4.7 (C++11) compilation.

Fix GCC 4.7 (C++11) compilation.

Cherry-pick of 90d12ab92e857dbb437cd4e0c132369d27947cbc from v8 git.

Original patch by Olivier Goffart <ogoffart@kde.org>.

BUG=v8:2136
TEST=

Review URL: https://chromiumcodereview.appspot.com/10387210

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@11600 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

Change-Id: Ib0f30c83596b66db053600cdae4ca86814046dc4
Reviewed-by: Girish Ramakrishnan <girish.1.ramakrishnan@nokia.com>
Reviewed-by: Konstantin Ritt <ritt.ks@gmail.com>
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>