Fix bug parsing media descriptions: the final field isn't a codec type for any of DTLS/SCTP, SCTP, or SCTP/DTLS.
Fix bug parsing media descriptions: the final field isn't a codec type for any of DTLS/SCTP, SCTP, or SCTP/DTLS.

BUG=none
TEST=none
R=juberti@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/34029004

Cr-Original-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#8369}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 3341b401cce2b2e8dbec55bdae4261cf0fc19012

dcpang/fatline-libjingle,dcpang/fatline-libjingle,dcpang/fatline-libjingle,dcpang/fatline-libjingle,sippet/talk,sippet/talk,sippet/talk,sippet/talk,sippet/talk,dcpang/fatline-libjingle