Blink-side contiguous allocation of display items.

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/RuntimeEnabledFeatures.h"
 #include "platform/graphics/GraphicsContext.h"
 #include "platform/graphics/paint/DisplayItemList.h"
 #include "platform/graphics/paint/ScrollDisplayItem.h"
 
 namespace blink {
 
 ScrollRecorder::ScrollRecorder(GraphicsContext& context, const DisplayItemClientWrapper& client, PaintPhase phase, const IntSize& currentOffset)
     : m_client(client)
     , m_beginItemType(DisplayItem::paintPhaseToScrollType(phase))
     , m_context(context)
 {
     if (RuntimeEnabledFeatures::slimmingPaintEnabled()) {
         ASSERT(m_context.displayItemList());
         if (m_context.displayItemList()->displayItemConstructionIsDisabled())
             return;
-        m_context.displayItemList()->add(BeginScrollDisplayItem::create(m_client, m_beginItemType, currentOffset));
+        m_context.displayItemList()->createAndAppend<BeginScrollDisplayItem>(m_client, m_beginItemType, currentOffset);
     } else {
         BeginScrollDisplayItem scrollDisplayItem(m_client, m_beginItemType, currentOffset);
         scrollDisplayItem.replay(m_context);
     }
 }
 
 ScrollRecorder::~ScrollRecorder()
 {
     DisplayItem::Type endItemType = DisplayItem::scrollTypeToEndScrollType(m_beginItemType);
     if (RuntimeEnabledFeatures::slimmingPaintEnabled()) {
         ASSERT(m_context.displayItemList());
         if (!m_context.displayItemList()->displayItemConstructionIsDisabled()) {
             if (m_context.displayItemList()->lastDisplayItemIsNoopBegin())
                 m_context.displayItemList()->removeLastDisplayItem();
             else
-                m_context.displayItemList()->add(EndScrollDisplayItem::create(m_client, endItemType));
+                m_context.displayItemList()->createAndAppend<EndScrollDisplayItem>(m_client, endItemType);
         }
     } else {
         EndScrollDisplayItem endScrollDisplayItem(m_client, endItemType);
         endScrollDisplayItem.replay(m_context);
     }
 }
 
 } // namespace blink