tree ace2312bb26c1effc56371fad9deb70e18ecd3bf
parent c96b441a1e07dfa75c03a3c214f20d341ec97971
author David Pursehouse <dpursehouse@collab.net> 1506040084 +0900
committer David Pursehouse <dpursehouse@collab.net> 1506040487 +0900

RefUpdate: Protect against null ObjectId in ReceiveCommand

RefUpdate's onRefOperation method is invoked by RefOperationValidators
for every registered RefOperationValidationListener.

If one of those listeners passes a RefReceivedEvent that contains an
instance of ReceiveCommand that was initialized with null old or
new ObjectId, this results in a NullPointerException when the ObjectId
is dereferenced to get the name.

Protect against such misbehaving validators by translating any null
instance to ObjectId.zeroId().

Change-Id: Ib9399c2351af20b23f8c4481c7b067f3a4dcb688