Remove EmitPreconnectionHistograms supression.
Remove EmitPreconnectionHistograms supression.

r54795 fixed the underlying problem.

BUG=51079
TEST=None
Review URL: http://codereview.chromium.org/3061047

git-svn-id: http://src.chromium.org/svn/trunk/src@54798 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 7e16763189eafcdf9af0de554dfc0bfd01f78cd1
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser