Actual damages in copyright can be the profits the infringer made from the infringement or the profits the copyright owner lost due to the infringement, so first of all the potential damages (if there was copyright infringement...which is an allegation that as far as I know no one has even been able to guess what it might be) could be up to what Oracle would sell a license for, which I suspect could be a considerable amount. So, I'm not sure PJ is correct here about the potential damages being cut immensely, at least if Oracle asks for actual damages.
Second (and this is the part that is relevant to file sharing), actual damages can be difficult to calculate. It is often highly speculative how much an infringer profited from an infringement, or how much the copyright holder lost due to the infringement. To deal with this difficulty, US copyright law has a thing called STATUTORY DAMAGES. The plaintiff can elect to ask for statutory damages instead of actual damages, and the court is then allowed to come up with a damage number from a range specified by the statute. That range is from $750 to $30k per infringed work, with the court having discretion to drop the low end to $200 if the defendant was not aware and had no reason to believe they were infringing, or to raise the high end to $150k if the infringement was willful.
All the file sharing lawsuit damage awards have been statutory damages, and have involved many songs. Each song is a separate work, so if the court is nice and goes low ($750) but there were 40 songs, that's $30k. The two most prominent defendants, though, were blatantly guilty, and in one case lied under oath and tried to destroy evidence and tried to frame her kids for the infringement, so the court was not inclined to go for the low end of the statutory damages.
(Note that when the RIAA goes after a file sharer, they usually offer to settle for an amount that is under the minimum they would get from statutory damages, which is why if you are in fact guilty, you should settle).
In the case of Android, it would be likely that there would only be one work infringed (although maybe different libraries are different works, so maybe there are more...), and so even if Oracle got $150k/work, it would not be an amount that would be large for Google. Maybe this is what PJ was thinking of?