Add support of serving SCT on the server side in QUIC, gated by QUIC_VERSION_30.

net/quic/test_tools/crypto_test_utils_chromium.cc

 // Copyright 2013 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/quic/test_tools/crypto_test_utils.h"
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "net/base/net_errors.h"
 #include "net/base/test_data_directory.h"
@@ skipping 47 matching lines @@
     certs_[1] = kIntermediateCert;
   }
   ~FakeProofSource() override {}
 
   // ProofSource interface
   bool GetProof(const IPAddressNumber& server_ip,
                 const std::string& hostname,
                 const std::string& server_config,
                 bool ecdsa_ok,
                 const std::vector<std::string>** out_certs,
-                std::string* out_signature) override {
+                std::string* out_signature,
+                std::string* out_leaf_cert_sct) override {
     *out_certs = &certs_;
     *out_signature = kSignature;
     return true;
   }
 
  private:
   std::vector<std::string> certs_;
   DISALLOW_COPY_AND_ASSIGN(FakeProofSource);
 };
 
@@ skipping 76 matching lines @@
 }
 
 // static
 ProofVerifyContext* CryptoTestUtils::FakeProofVerifyContextForTesting() {
   return nullptr;
 }
 
 }  // namespace test
 
 }  // namespace net