Revert 56796 - Sbox IPC fix

      Tests failing on vista 

BUG=52682
TEST=included


Review URL: http://codereview.chromium.org/3142022

TBR=cpu@chromium.org
Review URL: http://codereview.chromium.org/3122031

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@56798 0039d316-1c4b-4281-b951-d872f2087c98