WebCrypto: Add algorithm normalization rules for RSASSA-PKCS1-v1_5.

Source/modules/crypto/HmacParams.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 27 matching lines @@
 Algorithm* HmacParams::hash()
 {
     if (!m_hash)
         m_hash = Algorithm::create(m_algorithm.hmacParams()->hash());
     return m_hash.get();
 }
 
 HmacParams::HmacParams(const WebKit::WebCryptoAlgorithm& algorithm)
     : Algorithm(algorithm)
 {
+    ASSERT(algorithm.hmacParams());
     ScriptWrappable::init(this);
 }
 
 } // namespace WebCore