gtk: Certificate viewer should show both A-label and U-label for CN and SubjectAltName IDNs

chrome/third_party/mozilla_security_manager/nsNSSCertHelper.h

Index: chrome/third_party/mozilla_security_manager/nsNSSCertHelper.h
diff --git a/chrome/third_party/mozilla_security_manager/nsNSSCertHelper.h b/chrome/third_party/mozilla_security_manager/nsNSSCertHelper.h
index 9c98fbddd95cd50814acfaffdc17348a7b1432e6..271d88eae0d4c44af6517e877747853637d1c2ef 100644
--- a/chrome/third_party/mozilla_security_manager/nsNSSCertHelper.h
+++ b/chrome/third_party/mozilla_security_manager/nsNSSCertHelper.h
@@ -81,6 +81,11 @@ std::string ProcessRawBytes(SECItem* data);
 // For fields which have the length specified in bits, rather than bytes.
 std::string ProcessRawBits(SECItem* data);
 
+// For host values, if they contain IDN Punycode-encoded A-labels, this will
+// return a string suitable for display that contains both the original and the
+// decoded U-label form.  Otherwise, the string will be returned as is.
+std::string ProcessIDN(const std::string& input);
+
 std::string DumpOidString(SECItem* oid);
 std::string GetOIDText(SECItem* oid);