[MERGE] Fix test suite regression on OSX in TestReadMergeableFromUrl.test_smart_server_connection_reset.

[Andrew Bennetts]

Andrew Bennetts has voted tweak.
Status is now: Conditionally approved
Comment:
A test for this would be nice.  I think you could probably make a good 
one using the _DisconnectingTCPServer in test_bundle.  Otherwise, this 
fix looks good to me.

For details, see: 
http://bundlebuggy.aaronbentley.com/project/bzr/request/%3Cm28wt8ol5x.fsf%40free.fr%3E
Project: Bazaar