Charlie with Spanish screenwriter Jose Lopez Rubio & Georgia Hale, c. 1930
I wasn't completely convinced that the girl in the middle was Georgia (she never looks like the dance hall girl from The Gold Rush in candid photos!), so I did a little research and found another photo (below), taken on the same day, of Rubio and Georgia after a tennis match (Georgia was a very good tennis player and is credited for introducing Charlie to the game). The above photo was taken on the tennis court of Charlie's Beverly Hills home.
Something interesting I noticed about this photo is that the sweater Georgia is wearing looks very similar to the sweater Charlie wore during Winston Churchill's visit in 1929 (below). It might not be exactly the same but it's close.