add Field.getDeclaredAnnotations default method for android classpath

Fixes Reflection test

FWIW, the two remaining failures (on mac, anyway) will be tougher to solve:
* Datagrams fails because android makes assumptions about the linux /sys/ filesystem that doesn't exist on darwin
* Misc fails because it can't find com.android.okhttp.HttpHandler, while constructing a URL.  This library will have to be included in the build instructions for android, as it seems to be distributed separately.