Fix segv in indirect reference table dump.

ReferenceTable::Dump is common code but can't handle NULLs. Process
IndirectReferenceTable's use so that it doesn't pass NULLs for removed
slots.
Improve unit tests.

Change-Id: Ia41375f8f2ecc907ceda8c39d146ce6ef607fb08
3 files changed
tree: 8d99894096a612c072b3bce521ae5ac24ffbbf7a
  1. build/
  2. jdwpspy/
  3. src/
  4. test/
  5. tools/
  6. .gitignore
  7. Android.mk