Blink-side contiguous allocation of display items.

Source/core/paint/ScrollRecorder.cpp

Index: Source/core/paint/ScrollRecorder.cpp
diff --git a/Source/core/paint/ScrollRecorder.cpp b/Source/core/paint/ScrollRecorder.cpp
index bbc320b683e32d46d749edacfadbc2ce4a72fa05..207f9f0dde562b2553ba1ed63fb0da4a6fa01f1d 100644
--- a/Source/core/paint/ScrollRecorder.cpp
+++ b/Source/core/paint/ScrollRecorder.cpp
@@ -21,7 +21,7 @@ ScrollRecorder::ScrollRecorder(GraphicsContext& context, const DisplayItemClient
         ASSERT(m_context.displayItemList());
         if (m_context.displayItemList()->displayItemConstructionIsDisabled())
             return;
-        m_context.displayItemList()->add(BeginScrollDisplayItem::create(m_client, m_beginItemType, currentOffset));
+        m_context.displayItemList()->createAndAppendIfNeeded<BeginScrollDisplayItem>(m_client, m_beginItemType, currentOffset);
     } else {
         BeginScrollDisplayItem scrollDisplayItem(m_client, m_beginItemType, currentOffset);
         scrollDisplayItem.replay(m_context);
@@ -35,7 +35,7 @@ ScrollRecorder::~ScrollRecorder()
         ASSERT(m_context.displayItemList());
         if (m_context.displayItemList()->displayItemConstructionIsDisabled())
             return;
-        m_context.displayItemList()->add(EndScrollDisplayItem::create(m_client, endItemType));
+        m_context.displayItemList()->createAndAppendIfNeeded<EndScrollDisplayItem>(m_client, endItemType);
     } else {
         EndScrollDisplayItem endScrollDisplayItem(m_client, endItemType);
         endScrollDisplayItem.replay(m_context);