Record UMA metrics for Must-Staple certificates on private roots

net/cert/asn1_util.h

Index: net/cert/asn1_util.h
diff --git a/net/cert/asn1_util.h b/net/cert/asn1_util.h
index 23bc2d2cf9039487381fbb4eb0746c06932b25fa..fb64bfbb58b38462872e5f7e911dc8b38d86bd07 100644
--- a/net/cert/asn1_util.h
+++ b/net/cert/asn1_util.h
@@ -43,6 +43,13 @@ NET_EXPORT_PRIVATE bool ExtractCRLURLsFromDERCert(
     base::StringPiece cert,
     std::vector<base::StringPiece>* urls_out);
 
+// HasTLSFeatureExtension parses the DER encoded certificate in |cert|
+// and extracts the TLS feature extension
+// (https://tools.ietf.org/html/rfc7633) if present. Returns true if the
+// TLS feature extension was present, and false if the extension was not
+// present or if there was a parsing failure.
+NET_EXPORT_PRIVATE bool HasTLSFeatureExtension(base::StringPiece cert);
+
 } // namespace asn1
 
 } // namespace net