Generate FMTP parameters for the H.264 codec.

webrtc/media/base/mediaconstants.cc

Index: webrtc/media/base/mediaconstants.cc
diff --git a/webrtc/media/base/mediaconstants.cc b/webrtc/media/base/mediaconstants.cc
index 2190a54d1009922acb0af7404de38c63433c9089..d6bb7e3d48a68dc6b07dd72cce37f61a57672a13 100644
--- a/webrtc/media/base/mediaconstants.cc
+++ b/webrtc/media/base/mediaconstants.cc
@@ -116,6 +116,12 @@ const char kVp8CodecName[] = "VP8";
 const char kVp9CodecName[] = "VP9";
 const char kH264CodecName[] = "H264";
 
+// RFC 6184 RTP Payload Format for H.264 video
+const char kH264FmtpProfileLevelId[] = "profile-level-id";
+const char kH264FmtpLevelAsymmetryAllowed[] = "level-asymmetry-allowed";
+const char kH264FmtpPacketizationMode[] = "packetization-mode";
+const char kH264ProfileLevelConstrainedBaseline[] = "42e01f";
+
 const int kDefaultVp8PlType = 100;
 const int kDefaultVp9PlType = 101;
 const int kDefaultH264PlType = 107;