Revert 252837 "trial run of vs2013 with iterator debugging off t..."

> trial run of vs2013 with iterator debugging off to see if browser_tests are timing-related
> 
> BUG=
> 
> Review URL: https://codereview.chromium.org/165693005

TBR=scottmg@chromium.org

Review URL: https://codereview.chromium.org/176203003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252844 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 252844