GitLab

Add metric recording in CPM for how long it takes to load a page.

BUG=130212
TEST=included browsertest


Review URL: https://chromiumcodereview.appspot.com/10829078

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@151197 0039d316-1c4b-4281-b951-d872f2087c98