RtpRtcp allows to register header extension by name

webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.h

Index: webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.h
diff --git a/webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.h b/webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.h
index 8c211e4d9cd78c648bfe6dc9615e715654bb46fa..12c840ae14aa1adb9bb250f9468e5c42e3f80658 100644
--- a/webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.h
+++ b/webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.h
@@ -13,6 +13,7 @@
 
 #include <list>
 #include <set>
+#include <string>
 #include <utility>
 #include <vector>
 
@@ -59,6 +60,8 @@ class ModuleRtpRtcpImpl : public RtpRtcp {
   int32_t RegisterSendRtpHeaderExtension(RTPExtensionType type,
                                          uint8_t id) override;
 
+  bool RegisterRtpHeaderExtension(const std::string& type, uint8_t id) override;
+
   int32_t DeregisterSendRtpHeaderExtension(RTPExtensionType type) override;
 
   // Get start timestamp.