[Pidgin] #14936: Port to Farstream

[Pidgin]

#14936: Port to Farstream
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 Reporter:  ocrete                  |        Owner:  Maiku          
     Type:  patch                   |       Status:  new            
Milestone:  Patches Needing Review  |    Component:  Voice and Video
  Version:  2.10.1                  |   Resolution:                 
 Keywords:                          |  
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Comment(by ocrete):

 Actually, in farsight2, there is only a fs_stream_set_remote_candidates().
 In Farstream, this has been split into fs_stream_add_remote_candidates()
 and fs_stream_force_remote_candidates(). The main difference between them
 is that _force_() implies that there is no negotiation, while _add_()
 gives them to some negotiation engine (like libnice).

 So this change is purely for Farstream.

 The only bit of the patch that can be used with Farsight2 is the use of
 the default element properties from Farsight2/Farstream, but even this
 requires a relatively recent version of Farsight2.

 The rest is pure porting. Farstream has a couple new APIs that can reduce
 the amount of code a bit, but I didn't even port to those.

 We can add ifdefs all over, and since Farsight2 and Farstream are not
 parallel installable, there is no point in having separate backends.

-- 
Ticket URL: <http://developer.pidgin.im/ticket/14936#comment:3>
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