[webcrypto] Add the KeyAlgorithm interface.

Source/modules/crypto/Key.h

Index: Source/modules/crypto/Key.h
diff --git a/Source/modules/crypto/Key.h b/Source/modules/crypto/Key.h
index 6fb89cc775e0644ea3e84b9a8cb62de16da89b05..a9cafb501331e3cc3f6b7392a5e225365cbf98be 100644
--- a/Source/modules/crypto/Key.h
+++ b/Source/modules/crypto/Key.h
@@ -42,10 +42,10 @@
 
 namespace WebCore {
 
-class Algorithm;
 class CryptoResult;
+class KeyAlgorithm;
 
-class Key : public RefCountedWillBeGarbageCollectedFinalized<Key>,  public ScriptWrappable {
+class Key : public RefCountedWillBeGarbageCollectedFinalized<Key>, public ScriptWrappable {
 public:
     static PassRefPtrWillBeRawPtr<Key> create(const blink::WebCryptoKey& key)
     {
@@ -56,7 +56,7 @@ public:
 
     String type() const;
     bool extractable() const;
-    Algorithm* algorithm();
+    KeyAlgorithm* algorithm();
     Vector<String> usages() const;
 
     const blink::WebCryptoKey& key() const { return m_key; }
@@ -75,7 +75,7 @@ protected:
     explicit Key(const blink::WebCryptoKey&);
 
     const blink::WebCryptoKey m_key;
-    RefPtrWillBeMember<Algorithm> m_algorithm;
+    RefPtrWillBeMember<KeyAlgorithm> m_algorithm;
 };
 
 } // namespace WebCore