appears master also has this problem so we hydrate things twice

[tw-mbp-peiyu pants (master)]$ cat x4.log |grep watchman_client
hydrate_struct UnhydratedStruct(address=BuildFileAddress(src/python/pants/pantsd/BUILD, watchman), struct=PythonLibraryAdaptor(dependencies=['src/python/pants/util:dirutil', 'src/python/pants/util:retry', ':process_manager', ':watchman_client'], name='watchman', sources=['watchman.py'], type_alias=u'python_library'), dependencies=[])
resolve_unhydrated_struct src/python/pants/pantsd:watchman_client
hydrate_struct UnhydratedStruct(address=BuildFileAddress(src/python/pants/pantsd/BUILD, watchman_client), struct=PythonLibraryAdaptor(dependencies=['3rdparty/python:pywatchman'], name='watchman_client', sources=['watchman_client.py'], type_alias=u'python_library'), dependencies=[])
hydrate_struct UnhydratedStruct(address=BuildFileAddress(src/python/pants/pantsd/BUILD, watchman), struct=PythonLibraryAdaptor(dependencies=['src/python/pants/util:dirutil', 'src/python/pants/util:retry', ':process_manager', ':watchman_client'], name='watchman', sources=['watchman.py'], type_alias=u'python_library'), dependencies=[])
resolve_unhydrated_struct BuildFileAddress(src/python/pants/pantsd/BUILD, watchman_client)
hydrate_struct UnhydratedStruct(address=BuildFileAddress(src/python/pants/pantsd/BUILD, watchman_client), struct=PythonLibraryAdaptor(dependencies=['3rdparty/python:pywatchman'], name='watchman_client', sources=['watchman_client.py'], type_alias=u'python_library'), dependencies=[])

the 2nd time in python it is still

BuildFileAddress

, do we have something to turn

Address

into

BuildFileAddress

?