Collate more of the low-level class lookups.

I pulled out all the initialization code that I could find that was
merely looking up class and member names during early VM initialization,
putting them all in a new file, InitRefs.c. I didn't do any real restructuring
of the code, though. That will come in a follow-up.

This was instigated by discussion surrounding bug #3500987, but it's not
directly related to it.

Change-Id: I59e93e552d29a5518f2cc4e1e30c4a8d51750d7b
15 files changed