Credential Manager: Add a 'formData' property to LocalCredential.

Source/modules/credentialmanager/LocalCredential.h

 // Copyright 2014 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 LocalCredential_h
 #define LocalCredential_h
 
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "bindings/core/v8/SerializedScriptValue.h"
 #include "modules/credentialmanager/Credential.h"
 #include "platform/heap/Handle.h"
 #include "platform/weborigin/KURL.h"
 
 namespace blink {
 
+class DOMFormData;
 class WebLocalCredential;
 
 class LocalCredential final : public Credential {
     DEFINE_WRAPPERTYPEINFO();
 public:
     static LocalCredential* create(const String& id, const String& password, ExceptionState& exceptionState)
     {
         return create(id, password, emptyString(), emptyString(), exceptionState);
     }
 
     static LocalCredential* create(const String& id, const String& password, const String& name, ExceptionState& exceptionState)
     {
         return create(id, password, name, emptyString(), exceptionState);
     }
 
     static LocalCredential* create(const String& id, const String& password, const String& name, const String& avatar, ExceptionState&);
     static LocalCredential* create(WebLocalCredential*);
 
     // LocalCredential.idl
     const String& password() const;
+    DOMFormData* formData() const { return m_formData.get(); };
+
+    virtual void trace(Visitor*) override;
 
 private:
     LocalCredential(WebLocalCredential*);
     LocalCredential(const String& id, const String& password, const String& name, const KURL& avatar);
+
+    // FIXME: Reconsider use of GarbageCollectedFinalized once this can be a Member.
+    RefPtrWillBeMember<DOMFormData> m_formData;
 };
 
 } // namespace blink
 
-#endif // Credential_h
+#endif // LocalCredential_h