Support java annotation proccessors

The codebase is growing more uses of annotation processors,
through a mixture of LOCAL_ADDITIONAL_DEPENDENCIES and
LOCAL_JACK_FLAGS.  Add LOCAL_ANNOTATION_PROCESSORS and handle
the rest in the build system.

For now we also need LOCAL_ANNOTATION_PROCESSOR_CLASSES to
work around bad behavior in grok (b/25860419).

Test: m -j java
Change-Id: I465b021e65d25ed3ea517333a82ec4ebd63fc038