[Merge] lp:~stgraber/upstart/upstart-prctl into lp:upstart

[James Hunt]

- Could you change:

    "Unable to mark us as a subreaper"

  ... to:

    "Unable to register as subreaper"

- I'd prefer the event to be called something like 'child-subreaper-failed', to allow for the fact
  that other systems may implement it in ways other than prctl. And it's shorter :)

- There is an extraneous C++ comment that can be removed:

    // Emit prctl-subreaper-failed event

-- 
https://code.launchpad.net/~stgraber/upstart/upstart-prctl/+merge/136759
Your team Upstart Reviewers is requested to review the proposed merge of lp:~stgraber/upstart/upstart-prctl into lp:upstart.