Merged revisions 335991 via svnmerge from

Merged revisions 335991 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/10

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  r335991 | irroot | 2011-09-15 10:29:12 +0200 (Thu, 15 Sep 2011) | 17 lines

  Merged revisions 335978 via svnmerge from
  https://origsvn.digium.com/svn/asterisk/branches/1.8

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    r335978 | irroot | 2011-09-15 10:15:22 +0200 (Thu, 15 Sep 2011) | 11 lines

    lock the channel before calling ast_bridged_channel() to prevent a seg fault.

    AMI agents list called on shutdown causes a segfault, introducing proper locking
    will prevent this.

    (closes issue ASTERISK-18092)

    Reported by: agustina
    Patches: chan_agent.patch (License #5041) patch uploaded by irroot
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@335993 65c4cc65-6c06-0410-ace0-fbb531ad65f3