Revert "Move ViewDisplayList to GraphicsLayer"

Source/platform/graphics/paint/DisplayItemList.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 DisplayItemList_h
-#define DisplayItemList_h
-
-#include "platform/PlatformExport.h"
-#include "platform/graphics/paint/DisplayItem.h"
-#include "wtf/HashSet.h"
-#include "wtf/PassOwnPtr.h"
-#include "wtf/Vector.h"
-
-namespace blink {
-
-typedef Vector<OwnPtr<DisplayItem> > PaintList;
-
-class PLATFORM_EXPORT DisplayItemList {
-    WTF_MAKE_NONCOPYABLE(DisplayItemList);
-public:
-    DisplayItemList() { };
-
-    const PaintList& paintList();
-    void add(WTF::PassOwnPtr<DisplayItem>);
-    void invalidate(DisplayItemClient);
-
-#ifndef NDEBUG
-    void showDebugData() const;
-#endif
-
-private:
-    PaintList::iterator findDisplayItem(PaintList::iterator, const DisplayItem&);
-    bool wasInvalidated(const DisplayItem&) const;
-    void updatePaintList();
-
-    PaintList m_paintList;
-    HashSet<DisplayItemClient> m_paintListRenderers;
-    HashSet<DisplayItemClient> m_invalidated;
-    PaintList m_newPaints;
-};
-
-} // namespace blink
-
-#endif // DisplayItemList_h