Update from chromium https://crrev.com/302282

net/cert/x509_certificate_ios.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/cert/x509_certificate.h"
 
 #include <CommonCrypto/CommonDigest.h>
 #include <Security/Security.h>
 
 #include <cert.h>
@@ skipping 232 matching lines @@
 }
 
 // static
 void X509Certificate::GetPublicKeyInfo(OSCertHandle cert_handle,
                                        size_t* size_bits,
                                        PublicKeyType* type) {
   x509_util_ios::NSSCertificate nss_cert(cert_handle);
   x509_util::GetPublicKeyInfo(nss_cert.cert_handle(), size_bits, type);
 }
 
+// static
+bool X509Certificate::IsSelfSigned(OSCertHandle cert_handle) {
+  x509_util_ios::NSSCertificate nss_cert(cert_handle);
+  crypto::ScopedSECKEYPublicKey public_key(
+      CERT_ExtractPublicKey(nss_cert.cert_handle()));
+  if (!public_key.get())
+    return false;
+  return SECSuccess == CERT_VerifySignedDataWithPublicKey(
+      &nss_cert.cert_handle()->signatureWrap, public_key.get(), NULL);
+}
+
 }  // namespace net