A picture of the whole plant would be helpful. Are there any flowers on it, or berries at the moment? edited to add - Wait, I see the berries now.
By the leaves alone I would have guessed a citrus of some sort, but not with those berries. Is it a shrub, tree or low plant? Do you remember what the flowers looked like?
What part of California are you in? Desert or seashore makes a big difference towards guessing what your plant might be.
