Though some of the images are blurry, the fruit looks just like that of the eastern prickly gooseberry (Ribes cynosbati), which is common in the eastern half of the US, but its a bit more complicated because you live in California.... There are several Californian species with fruit like this including the ground gooseberry (Ribes binominatum), hillside gooseberry (Ribes californicum) and Sierra gooseberry (Ribes roezlii), among others. Flower, habit and foliar details would need to be hammered out to get this plant identified to species. Still, I think it's safe to say it's a Ribes. If you can get more information about this plant please send it our way or share it with a local extension agent. 

Here's some folks that sell Californian Ribes: www.laspilitas.com/groups/ribes_currant_.... The fruit quality and flavor varies from species to species.

I hope this helps!

Jessie