Merge changes I3b881be8,I80d97bd5,Id115e8b2
am: b764f45fd9

* commit 'b764f45fd9758c8222bc08d7fa4944e8f7da6f40':
  Fix lint warnings.
  Note a 3.18 commit in neighbour_test.py.
  SOCK_DESTROY is no longer optional.