sdpmessage: add support for rtcp-fb attributes

Submitted by Tomasz Zajac

Link to original bug (#769628)

Description

Created attachment 332940
Add parsing of rtcp-fb attributes

There is no implementation for parsing rtcp-fb media attributes (like rtcp-fb-nack-pli or rtcp-fb-ccm-fir). If SDP contain such attribute, SDP parser should add relevant capability into RTP CAPS.
For example:
If SDP contains "a=rtcp-fb:96 nack pli", relevant rtp caps should contain rtcp-fb-nack-pli=true. As it is now, it ends up as "a-rtcp-fb=(string)"96\ nack\ pli".

Please see enclosed patch which implements the missing feature.

Patch 332940, "Add parsing of rtcp-fb attributes":
0001-Parse-rtcp-fb-media-attributes.patch

Version: 1.8.1