Is any code written by a High School student automatically uncopyrightable?
But something like the rangeCheck function is what you'd get if you asked a junior programmer "before you're going to access that datastructure make sure your within its range". Furthermore it's a completely irrelevant part of Android as a whole which gave Google no competitive advantage whatsoever.
First, trivial bits of a work with minimal creative expression are not covered by copyright. This sort of thing is called "de minimis". You can't assert copyright, for example, on the words "You're welcome" just because they appeared in a work you've copyrighted. If you could, you'd certainly be rich, but that kind of rent seeking is a little beyond the purpose of copyright. Rebecca Black's "Friday", as awful as it may be, is full of creative expression. Google is arguing that rangeCheck is extremely minimal and perfunctory, kind of like if it were accused of copying the word "Partying" from Rebecca Black.
Second, IIRC Oracle is making a big deal out of this copying. Google was willing to pay a statuory fee for its indiscretion just like it would if it had actually used a trivial function from a high schooler, but Oracle is trying to make this function out to be a difficult and important part of Java, meaning it deserves a share of Google's profits.
Actually, the song was created by ARK Music Factory, as described on their Wikipedia page: http://en.wikipedia.org/wiki/ARK_Music_Factory
Rebecca Black's parents paid a couple thousand bucks for the privilege of having their daughter sing it and make a music video around it.
As there's only 9 lines of code, that's quantitatively small. The continual references to 'high school programmer' is to argue that it's also qualitatively small. Hence, de minimus.
I doubt that a) Rebecca Black came out with it in two minutes and b) hers is the most obvious implementation of "song".
If I could give you a vague description of "Friday" and you could immediately go and produce the exact lyrics and melody that Black did, I'd say it wouldn't deserve copyright protection either. Of course, "Friday" is far more complex than that.