Suppress uninits on layout tests
BUG=312332
TBR=bruening
NOTRY=true

Review URL: https://codereview.chromium.org/47603010

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@231347 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 231347