Add content type extension to capabilities

webrtc/media/engine/webrtcvideoengine2.cc

Index: webrtc/media/engine/webrtcvideoengine2.cc
diff --git a/webrtc/media/engine/webrtcvideoengine2.cc b/webrtc/media/engine/webrtcvideoengine2.cc
index 087fc4e011d7a7066534e4a892238a93f0ee4be5..be6aecc521ca814de005a25aa07fa45c168d0a30 100644
--- a/webrtc/media/engine/webrtcvideoengine2.cc
+++ b/webrtc/media/engine/webrtcvideoengine2.cc
@@ -503,6 +503,9 @@ RtpCapabilities WebRtcVideoEngine2::GetCapabilities() const {
   capabilities.header_extensions.push_back(
       webrtc::RtpExtension(webrtc::RtpExtension::kPlayoutDelayUri,
                            webrtc::RtpExtension::kPlayoutDelayDefaultId));
+  capabilities.header_extensions.push_back(

[brandtr, 2017/04/12 16:22:10]

Will this addition launch the header extension in the default SDP?

+        webrtc::RtpExtension(webrtc::RtpExtension::kVideoContentTypeUri,
+                             webrtc::RtpExtension::kVideoContentTypeDefaultId));
   return capabilities;
 }