[webcrypto] Some fixes for HMAC

content/renderer/webcrypto/webcrypto_util.h

 // Copyright (c) 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.
 
 #ifndef CONTENT_RENDERER_WEBCRYPTO_WEBCRYPTO_UTIL_H_
 #define CONTENT_RENDERER_WEBCRYPTO_WEBCRYPTO_UTIL_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 76 matching lines @@
 // Creates an AES-CBC algorithm whose parameters struct is compatible with key
 // generation.
 CONTENT_EXPORT blink::WebCryptoAlgorithm CreateAesCbcKeyGenAlgorithm(
     unsigned short key_length_bits);
 
 // Creates an AES-GCM algorithm whose parameters struct is compatible with key
 // generation.
 blink::WebCryptoAlgorithm CreateAesGcmKeyGenAlgorithm(
     unsigned short key_length_bits);
 
+// Returns the internal block size for SHA-*
+unsigned int ShaBlockSizeBytes(blink::WebCryptoAlgorithmId hash_id);
+
 }  // namespace webcrypto
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_WEBCRYPTO_WEBCRYPTO_UTIL_H_