In good Android tradition, every major version is followed by a series of build releases intended to quickly fix a small batches of issues. These updates usually come out to cure critical bugs, but sometimes they're just cleaning up a few relatively trivial mistakes. AOSP was just updated with a brand new version, tagged 5.1.0_r3. We've generated a changelog to show just what's different.

Unfortunately, there don't appear to be any commits targeting the things most people are complaining about: an aggressive process killer, things that cause battery drain, or the infamous "memory leak." Most of the fixes are related to bugs in the way SIM cards are handled, almost certainly the side effect of adding multiple-carrier support. One other fairly interesting change has to do with a bug in the TrustAgent API that couldn't be resolved properly, resulting in it being hidden from the API 22 SDK.

Strangely, the tags jump from r1 to r3, with no sign whatsoever of r2. It's likely that r2 slipped through the cracks and wasn't uploaded; but it probably lines up with LMY47E, which corresponds to a recent Nexus 6 factory image.

There are only 12 functional commits (not including updates to the build number), so it only takes a couple of minutes to look through all of them in depth. Check out the full list at the link below.

Source: Changelog