Implement HKDF for WebCrypto (blink-side)

public/platform/WebCryptoKeyAlgorithmParams.h

 /*
  * Copyright (C) 2014 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 37 matching lines @@
     virtual void setAlgorithm(const char*, const WebCryptoAlgorithm&) = 0;
     virtual void setUint8Array(const char*, const WebVector<unsigned char>&) = 0;
 };
 
 enum WebCryptoKeyAlgorithmParamsType {
     WebCryptoKeyAlgorithmParamsTypeNone,
     WebCryptoKeyAlgorithmParamsTypeHmac,
     WebCryptoKeyAlgorithmParamsTypeAes,
     WebCryptoKeyAlgorithmParamsTypeRsaHashed,
     WebCryptoKeyAlgorithmParamsTypeEc,
+    WebCryptoKeyAlgorithmParamsTypeKdf,

[eroman, 2015/01/07 00:40:31]

Same comment as earlier.

[nharper, 2015/01/08 00:58:40]

Done.

 };
 
 class WebCryptoKeyAlgorithmParams {
 public:
     virtual ~WebCryptoKeyAlgorithmParams() { }
     virtual WebCryptoKeyAlgorithmParamsType type() const
     {
         return WebCryptoKeyAlgorithmParamsTypeNone;
     }
 
@@ skipping 131 matching lines @@
         case WebCryptoNamedCurveP521:
             dict->setString("namedCurve", "P-521");
             break;
         }
     }
 
 private:
     const WebCryptoNamedCurve m_namedCurve;
 };
 
+class WebCryptoKdfKeyAlgorithmParams : public WebCryptoKeyAlgorithmParams {

[eroman, 2015/01/07 00:40:31]

Same comment as earlier. I don't think there is value in having an empty params
structure.

[nharper, 2015/01/08 00:58:39]

Done.

+public:
+    virtual WebCryptoKeyAlgorithmParamsType type() const
+    {
+        return WebCryptoKeyAlgorithmParamsTypeKdf;
+    }
+
+    virtual void writeToDictionary(WebCryptoKeyAlgorithmDictionary* dict) const
+    {
+        return;
+    }
+};
+
 } // namespace blink
 
 #endif