data-mm-id=”_ql5611l9j”>Justin Herbert did not throw a single pass or take one snap during the Los Angeles Chargers' preseason schedule. However, new head coach Jim Harbaugh already knows his starting quarterback can stay calm under pressure.Harbaugh said Sunday that "11 or 12 of our players" were trapped in the elevator of the team's Dallas hotel on Friday night. Herbert was one of the unlucky Chargers who spent two hours in the elevator before being guided out through ceiling panels to an adjacent elevator by Dallas Fire-Rescue.Harbaugh said he just missed taking that elevator. While watching everyone emerge from what he called a "test of wills," the Chargers coach was most impressed by one individual — Herbert."And it was hot," Harbaugh tol…