Autofill metrics improvements:

* Added new metrics:
  - AUTOFILL_USERDATA_UPDATED
  - AUTOFILL_FIELD_CLASSIFICATION_MATCHES
  - FIELD_AUTOFILL_MATCH_SCORE
  - FIELD_AUTOFILL_NUM_FIELD_CLASSIFICATION_IDS
* Fixed how FIELD_CLASS_NAME is set for AUTOFILL_SERVICE_DISABLED_ACTIVITY
* Added extra info on some existing metrics:
  - FIELD_FLAGS on AUTOFILL_SESSION_STARTED
  - TYPE_CLOSE on AUTOFILL_REQUEST to indicate a null response from service
  - FIELD_AUTOFILL_NUM_FIELD_CLASSIFICATION_IDS on AUTOFILL_REQUEST to indicate the number of ids in a
    field classfification request

Bug: 70241978
Test: verified output of 'adb shell logcat -b events | grep sysui' while
      running CTS tests associated with the changes

Change-Id: I05d8d0325e9b338dd3d874e5b95a08cedf4b271c