Use display_email() for Uber Tray messages.

BUG=124087
TEST=manually

Review URL: https://chromiumcodereview.appspot.com/10388171

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@137721 0039d316-1c4b-4281-b951-d872f2087c98
  void NotifyRefreshClock() {
    ash::ClockObserver* observer = tray_->clock_observer();
    if (observer)
      observer->Refresh();
  }

  void NotifyRefreshClock() {
    ash::ClockObserver* observer = tray_->clock_observer();
    if (observer)
      observer->Refresh();
  }
