Add unknown period enum value in CarWatchdog atoms.

- Address some minor nits.

Test: Build is okay.
Bug: 189508862
Bug: 184310189
Change-Id: If1ae775cce57056cf044e7b391a469c5d984bcbc
(cherry picked from commit 4d40c44a2710568bc53903b1146a000c5dd0e38c)
1 file changed
tree: 8da744307cb6c4b3bc2c4aff5b8b3bc16b9d2e9c
  1. stats/
  2. OWNERS