[IndexedDB] Use consistent enums on both sides of IPC.

public/platform/WebIDBCursor.h

 /*
  * Copyright (C) 2010 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:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 19 matching lines @@
 #include "WebIDBCallbacks.h"
 #include "WebIDBKey.h"
 #include "WebString.h"
 
 namespace blink {
 
 // See comment in WebIDBFactory for a high level overview these classes.
 class WebIDBCursor {
 public:
     virtual ~WebIDBCursor() { }
-
-    enum Direction {
-        Next = 0,
-        NextNoDuplicate = 1,
-        Prev = 2,
-        PrevNoDuplicate = 3,
-        DirectionLast = PrevNoDuplicate
-    };
-
     virtual void advance(unsigned long, WebIDBCallbacks*) { BLINK_ASSERT_NOT_REACHED(); }
     virtual void continueFunction(const WebIDBKey&, const WebIDBKey& primaryKey, WebIDBCallbacks*) { BLINK_ASSERT_NOT_REACHED(); }
     virtual void postSuccessHandlerCallback() { } // Only used in frontend.
 
 protected:
     WebIDBCursor() { }
 };
 
 } // namespace blink
 
 #endif // WebIDBCursor_h