Write stats when background dexopt job is ended.

Bug: 229966126
Test: -
  1. Flash the device.
  2. m statsd_testdrive
  3. statsd_testdrive 467
  4. adb shell cmd jobscheduler run android 801
  5. Wait for it to complete.
  6. See the following output:
    metric_id: 1111
    event_metrics {
      data {
        aggregated_atom_info {
          atom {
            background_dexopt_job_ended {
              status: STATUS_JOB_FINISHED
              cancellation_reason: STOP_REASON_UNDEFINED
              duration_ms: 25748
              duration_including_sleep_ms: 25748
            }
          }
          elapsed_timestamp_nanos: 205806342268
        }
      }
    }
    is_active: true
  7. statsd_testdrive 467
  8. adb shell cmd jobscheduler run android 800
  9. adb shell cmd jobscheduler timeout android 800
  10. See the following output:
    metric_id: 1111
    event_metrics {
      data {
        aggregated_atom_info {
          atom {
            background_dexopt_job_ended {
              status: STATUS_ABORT_BY_CANCELLATION
              cancellation_reason: STOP_REASON_TIMEOUT
              duration_ms: 5080
              duration_including_sleep_ms: 5080
            }
          }
          elapsed_timestamp_nanos: 261463072772
        }
      }
    }
    is_active: true
Change-Id: I82542de3a514e3f71a28c34a1e7da2b8d7980214