Port DirectBuffer trick from ScrubDroid

First attempt at porting the Direct Buffer trick from ScrubDroid into
DroidBench.  It builds, but the application crashes. That said, the
HashMapAccess1 that I built exhibited the same behaviour. Is it normal?

Let me know how this goes and what might need be fixed.

Signed-off-by: Olivier Mehani <olivier.mehani@nicta.com.au>