x/review/git-codereview: commit-msg hook doesn't play well with Signed-off-by lines

[minux]

For example, git commit -s will generate this log message:

    test: test commit

    Signed-off-by: Shenghou Ma <minux@golang.org>

    Change-Id: I3545610fc076ab9da46bb5ed571a49730a5075dc

However, it should look this instead, which is generated by the official gerrit commit-msg hook:

    test: test commit

    Change-Id: I3545610fc076ab9da46bb5ed571a49730a5075dc    
    Signed-off-by: Shenghou Ma <minux@golang.org>

[r5d]

I think this is address in golang/review@2e4fd9a

Close this issue?