Starbucks' turnaround is making progress, and protein is playing a role. The coffee chain said that its fourth-quarter comparable sales rose 1% globally — the first time in seven quarters that Starbucks has reported an increase. Comparable sales in the US were flat. New protein-heavy drinks were one of the drivers. Starbucks launched protein cold foam and protein lattes at the end of September, CEO Brian Niccol said on the company's earnings call on Wednesday. Starbucks had previously said it