Merge branch 'stable-2.12' into stable-2.13

* stable-2.12:
  Cancel periodic cleanup task on plugin unload
  Remove source_under_test to comply with new BUCK version

Change-Id: I0d4f1a0bc274b3f58f1fdb1f8d9dfb8d1bfa46e2
tree: 5ee96c9cca5d96f22b8250d1fca72932d406d270
  1. .buckconfig
  2. .gitignore
  3. .settings/
  4. BUCK
  5. LICENSE
  6. lib/
  7. src/