My impression is that it's just Oracle's lawyers bitching about failing to outlaw what's been common practice for decades (if you're not allowed to reverse engineer an API then the PC clone would never have happened and the world of computing would look very different, and probably be way more expensive than it is now), and they're clutching at straws.
The fact is that Google has done zero harm to Oracle. If anything they've revived their flagging fortunes regarding Java. It was already sinking into irrelevance by the time Android rolled around, and when it did suddenly there was demand for people with Java know-how again.
Fair use is fair. Deal with it.
Biting the hand that feeds IT
