No.. that's what a stupid and illegal protest looks like. You can peacefully protest in public as much as you want, it's your right under the first amendment. This does not extend into private property. If you don't have permission from the property owner, that's no longer a protest, that's trespassing. One could argue that the whole thing is a meta-protest (along with the arrest and the media coverage) which would be more or less correct, but that's not what you're arguing.

See https://www.aclu.org/know-your-rights/protesters-rights

Anyway, if the protestors actually believe they changed minds with this, I will forever be disappointed by Google's hiring practices.