[webcrypto] Check for empty key usages *after* key creation rather than before, to match the spec's…

components/webcrypto/algorithms/secret_key_util.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 "components/webcrypto/algorithms/secret_key_util.h"
 
 #include <openssl/rand.h>
 
 #include "components/webcrypto/algorithms/util.h"
 #include "components/webcrypto/blink_key_handle.h"
@@ skipping 32 matching lines @@
                                 const blink::WebCryptoKeyAlgorithm& algorithm,
                                 bool extractable,
                                 blink::WebCryptoKeyUsageMask usages,
                                 blink::WebCryptoKey* key) {
   *key = blink::WebCryptoKey::create(CreateSymmetricKeyHandle(key_data),
                                      blink::WebCryptoKeyTypeSecret, extractable,
                                      algorithm, usages);
   return Status::Success();
 }
 
-Status CheckSecretKeyCreationUsages(
-    blink::WebCryptoKeyUsageMask all_possible_usages,
-    blink::WebCryptoKeyUsageMask actual_usages) {
-  return CheckKeyCreationUsages(all_possible_usages, actual_usages,
-                                EmptyUsagePolicy::REJECT_EMPTY);
-}
-
 void WriteSecretKeyJwk(const CryptoData& raw_key_data,
                        const std::string& algorithm,
                        bool extractable,
                        blink::WebCryptoKeyUsageMask usages,
                        std::vector<uint8_t>* jwk_key_data) {
   JwkWriter writer(algorithm, extractable, usages, "oct");
   writer.SetBytes("k", raw_key_data);
   writer.ToJson(jwk_key_data);
 }
 
@@ skipping 11 matching lines @@
   std::string jwk_k_value;
   status = jwk->GetBytes("k", &jwk_k_value);
   if (status.IsError())
     return status;
   raw_key_data->assign(jwk_k_value.begin(), jwk_k_value.end());
 
   return Status::Success();
 }
 
 }  // namespace webcrypto