[Buildbot] #3582: cancel buildrequest does not work in the UI

[Buildbot trac]

#3582: cancel buildrequest does not work in the UI
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Reporter:  tardyp  |      Owner:
    Type:  defect  |     Status:  new
Priority:  major   |  Milestone:  0.9.0
 Version:  master  |   Keywords:
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 cancel buildrequest gives error in the browser console
 (buildrequest.control does not exist)

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Ticket URL: <http://trac.buildbot.net/ticket/3582>
Buildbot <http://buildbot.net/>
Buildbot: build/test automation