In the article, it said that the device used could extract data regardless of whether the phone was password-protected or not. Looks like it's time to start encrypting our cellphone data as well.
I don't recall any mention of the specific methods used in California, but in this case the officer took the phone when he arrested the person, so presumably the police had quite a long time to muck about with it. Here is one of the original articles covering the California Supreme Court ruling: