重构代码；修改mapId为-1的exam_status表，表示考试状态

endian11

2020-08-13 a927c72c0f06ef5bd771e5ae00bc35155c271762

 app/src/main/java/safeluck/drive/evaluation/DB/exam_status/ExamStatusWorkRepo.java

@@ -61,4 +61,13 @@
            }
        });
    }

    public void deleteAll() {
        WorkRoomDataBase.dataBaseWriteExecutor.execute(new Runnable() {
            @Override
            public void run() {
                examStatusDao.deleteAll();
            }
        });
    }
}