It probably seemed relatively remote when Sun was still around, as Schwartz and Sun had a history of being very friendly to open-source philosophies. Most viewed Sun's patents as defensive. Schwartz has written about how the patents kept Sun out of this mess before -- Microsoft came and said "Cough up because OpenOffice violates our patents" and Schwartz countered with "O RLY, well, while we're at it, why don't we discuss licensing for our Java-related patents re: .NET", etc. But now what used to be Sun is the aggressor.

Oracle bought Sun and everyone was concerned because Oracle is very evil.

OK but it's not convincing to think Google would have thought, oh Sun is a company that is nice to open source, so lets base our whole Android operating environment on this open source friendly Java language and JVM and disregard any possibility of being sued. I would think such companies would think about the possibility of someone else taking over or generally anything else happening. Its unprofessional to base your business decision on something as vague as attitude. You need something more solid like an agreement - especially for something as big as Android.

So anyway my understanding is probably Google has some agreement or plan at hand for this situation. Ideas welcome.