If a reference name is not valid according to Git's rules for the allowable syntax, or it contains "//" because a typo on the client side introduced an unnecessary slash, reject the command with an error. Bug: issue 466 Change-Id: I89d8137a89225bc31813f5870d75568e5080b059 Signed-off-by: Shawn O. Pearce <sop@google.com>