Merged revisions 284477 via svnmerge from

Merged revisions 284477 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.8

........
  r284477 | twilson | 2010-09-01 13:44:36 -0500 (Wed, 01 Sep 2010) | 17 lines

  Fix SRTP for changing SSRC and multiple a=crypto SDP lines

  Adding code to Asterisk that changed the SSRC during bridges and masquerades
  broke SRTP functionality. Also broken was handling the situation where an
  incoming INVITE had more than one crypto offer. This patch caches the SRTP
  policies the we use so that we can change the ssrc and inform libsrtp of the
  new streams. It also uses the first acceptable a=crypto line from the incoming
  INVITE.

  (closes issue #17563)
  Reported by: Alexcr
  Patches:
        srtp.diff uploaded by twilson (license 396)
  Tested by: twilson

  Review: https://reviewboard.asterisk.org/r/878/
........

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@284479 65c4cc65-6c06-0410-ace0-fbb531ad65f3