Avoid NPE when trying to delete changes for a project After I5babf38b0, trying to delete a project fails in some occasions with a NPE when trying to open a connection to ReviewDb [1]. Using the ReviewDb provider to get an instance fixes the issue. [1] https://pastebin.com/9qf9Sntn Change-Id: I33d4cb86742df536f73c22ee67d0a2c6505d69f3