Legal Question in Employment Law in California

Only if it is actually meant as an unwelcome sexual advance.

It's crude, but expressive. Bosses are given leeway to be jerks, and such comments don't engender goodwill among employees. But it's not actionable unless it's meant in a sexual way.

Of course. But simple harassment is not 'illegal'. If it can be interpreted as a form of sexual, racial, ethnic or other discrimination or harassment, then it would be actionable. It would certainly be grounds for termination of the speaker as bad attitude and bad conduct by an 'at will' employee.