More MIPS fixes. Fibonacci and ExceptionTest work.

In this change:
- Fixed compilation of div-int and instance-of
- Fixed VERIFY_OBJECT to compile again
- Added stack space for passing extra function arguments for
  REF_ONLY_CALLEE_SAVE functions
- Fixed AbstractMethodErrorStub to match stack layout

Change-Id: I3d4540a3285a0acf49522ffc6f01d04b888bb8ef