Add an out parameter to VerifyCertificateChain for retrieving the trusted chain.

net/cert/internal/verify_certificate_chain.cc

 // Copyright 2015 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/internal/verify_certificate_chain.h"
 
 #include <memory>
 
 #include "base/logging.h"
 #include "net/cert/internal/name_constraints.h"
@@ skipping 465 matching lines @@
   certs->push_back(std::move(trust_anchors[0]));
   return true;
 }
 
 }  // namespace
 
 bool VerifyCertificateChain(
     const std::vector<scoped_refptr<ParsedCertificate>>& cert_chain,
     const TrustStore& trust_store,
     const SignaturePolicy* signature_policy,
-    const der::GeneralizedTime& time) {
+    const der::GeneralizedTime& time,
+    std::vector<scoped_refptr<ParsedCertificate>>* trusted_chain_out) {
   if (cert_chain.empty())
     return false;
 
   std::vector<scoped_refptr<ParsedCertificate>> full_chain = cert_chain;
 
   // Modify the certificate chain so that its root is a trusted certificate.
   if (!BuildSimplePathToTrustAnchor(trust_store, &full_chain))
     return false;
 
   // Verify the chain.
-  return VerifyCertificateChainAssumingTrustedRoot(full_chain, trust_store,
-                                                   signature_policy, time);
+  bool success = VerifyCertificateChainAssumingTrustedRoot(
+      full_chain, trust_store, signature_policy, time);
+  if (success && trusted_chain_out != nullptr)
+    *trusted_chain_out = std::move(full_chain);
+  return success;
 }
 
 }  // namespace net