[webcrypto] Add parameter parsing for RSA-PSS.

public/platform/WebCryptoAlgorithmParams.h

 /*
  * 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 214 matching lines @@
     virtual WebCryptoAlgorithmParamsType type() const { return WebCryptoAlgorithmParamsTypeRsaOaepParams; }
 
     bool hasLabel() const { return m_hasLabel; }
     const WebVector<unsigned char>& optionalLabel() const { return m_optionalLabel; }
 
 private:
     const bool m_hasLabel;
     const WebVector<unsigned char> m_optionalLabel;
 };
 
+class WebCryptoRsaPssParams : public WebCryptoAlgorithmParams {
+public:
+    explicit WebCryptoRsaPssParams(unsigned saltLengthBytes)
+        : m_saltLengthBytes(saltLengthBytes)
+    {
+    }
+
+    virtual WebCryptoAlgorithmParamsType type() const { return WebCryptoAlgorithmParamsTypeRsaPssParams; }
+
+    unsigned saltLengthBytes() const { return m_saltLengthBytes; }
+
+private:
+    const unsigned m_saltLengthBytes;
+};
+
 } // namespace blink
 
 #endif