Make DisplayItemClient an interface

third_party/WebKit/Source/core/paint/ScrollRecorder.cpp

 // Copyright 2015 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.
 
 #include "config.h"
 #include "core/paint/ScrollRecorder.h"
 
 #include "platform/graphics/GraphicsContext.h"
 #include "platform/graphics/paint/PaintController.h"
 #include "platform/graphics/paint/ScrollDisplayItem.h"
 
 namespace blink {
 
-ScrollRecorder::ScrollRecorder(GraphicsContext& context, const DisplayItemClientWrapper& client, PaintPhase phase, const IntSize& currentOffset)
+ScrollRecorder::ScrollRecorder(GraphicsContext& context, const DisplayItemClient& client, PaintPhase phase, const IntSize& currentOffset)
     : m_client(client)
     , m_beginItemType(DisplayItem::paintPhaseToScrollType(phase))
     , m_context(context)
 {
     m_context.paintController().createAndAppend<BeginScrollDisplayItem>(m_client, m_beginItemType, currentOffset);
 }
 
 ScrollRecorder::~ScrollRecorder()
 {
     m_context.paintController().endItem<EndScrollDisplayItem>(m_client, DisplayItem::scrollTypeToEndScrollType(m_beginItemType));
 }
 
 } // namespace blink