Change Notice: https://drupal.org/node/2087153
per& the Annotation discovery has always been a little wonky with regard to how we get the actual annotation class. I've never been happy with this, but I went and spent a little time with some Doctrine people and they showed me what looks to be a WAY better way that should support any autoloader long term. I had to change basically every plugin manager implementation, but it's a very minor and very sane change that I think makes using AnnotatedClassDiscovery WAY better, so I think this is a huge DX win.
Basically this removes the need to know what dir an Annotation class resides in, which is awesome.
PASSED: [[SimpleTest]]: [MySQL] 59,057 pass(es).
PASSED: [[SimpleTest]]: [MySQL] 58,682 pass(es).
PASSED: [[SimpleTest]]: [MySQL] 59,006 pass(es).