Add controlled setting indicator for default search engine configuration

This CL adds controlled setting indicators that show when the default
search engine configuration is managed by policy.

BUG=104955


Review URL: https://chromiumcodereview.appspot.com/11189088

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@163017 0039d316-1c4b-4281-b951-d872f2087c98
5 files changed