Improve Tethering and NativeDaemonConnector logging.

1. Deduplicate the Tethering message numbers, and use MessageUtils
   to convert them to strings.
2. Add a warning to NativeDaemonConnector when an unsolicited
   event is more than 500ms late or takes more than 500ms to
   process.

Bug: 27857665
Change-Id: I379aef9257027d1ccf30906e79c6389ef1f95420
3 files changed