[refactor] Replace custom utility function with base's "vector_as_array()"

content/child/webcrypto/nss/hmac_nss.cc

 // Copyright 2014 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 <cryptohi.h>
 #include <pk11pub.h>
 #include <secerr.h>
 #include <sechash.h>
 
 #include "base/logging.h"
+#include "base/stl_util.h"
 #include "content/child/webcrypto/algorithm_implementation.h"
 #include "content/child/webcrypto/crypto_data.h"
 #include "content/child/webcrypto/jwk.h"
 #include "content/child/webcrypto/nss/key_nss.h"
 #include "content/child/webcrypto/nss/sym_key_nss.h"
 #include "content/child/webcrypto/nss/util_nss.h"
 #include "content/child/webcrypto/status.h"
 #include "content/child/webcrypto/webcrypto_util.h"
 #include "crypto/secure_util.h"
 #include "third_party/WebKit/public/platform/WebCryptoAlgorithmParams.h"
@@ skipping 163 matching lines @@
 
     if (PK11_SignWithSymKey(
             sym_key, mechanism, &param_item, &signature_item, &data_item) !=
         SECSuccess) {
       return Status::OperationError();
     }
 
     DCHECK_NE(0u, signature_item.len);
 
     buffer->resize(signature_item.len);
-    signature_item.data = Uint8VectorStart(buffer);
+    signature_item.data = vector_as_array(buffer);
 
     if (PK11_SignWithSymKey(
             sym_key, mechanism, &param_item, &signature_item, &data_item) !=
         SECSuccess) {
       return Status::OperationError();
     }
 
     CHECK_EQ(buffer->size(), signature_item.len);
     return Status::Success();
   }
 
   virtual Status Verify(const blink::WebCryptoAlgorithm& algorithm,
                         const blink::WebCryptoKey& key,
                         const CryptoData& signature,
                         const CryptoData& data,
                         bool* signature_match) const OVERRIDE {
     std::vector<uint8_t> result;
     Status status = Sign(algorithm, key, data, &result);
 
     if (status.IsError())
       return status;
 
     // Do not allow verification of truncated MACs.
     *signature_match = result.size() == signature.byte_length() &&
-                       crypto::SecureMemEqual(Uint8VectorStart(result),
+                       crypto::SecureMemEqual(vector_as_array(&result),
                                               signature.bytes(),
                                               signature.byte_length());
 
     return Status::Success();
   }
 };
 
 }  // namespace
 
 AlgorithmImplementation* CreatePlatformHmacImplementation() {
   return new HmacImplementation;
 }
 
 }  // namespace webcrypto
 
 }  // namespace content