docker/docker — pull request #7983 by vbatts (2014-09-11 01:59:01+00:00)
Title: tarsum: TarSum is not the interface

don't export the exsisting TarSum struct and call the interface 'TarSum'
instead.
Per the comments in https://github.com/docker/docker/pull/7689

Signed-off-by: Vincent Batts