[Slimming Paint] Blink-side contiguous allocation of display items.

Source/core/paint/FloatClipRecorder.cpp

Index: Source/core/paint/FloatClipRecorder.cpp
diff --git a/Source/core/paint/FloatClipRecorder.cpp b/Source/core/paint/FloatClipRecorder.cpp
index 8797c065c2010645b3bf154ea8cc24d13bdd432e..5ea3c80ee7f7e143abd9d4f194e143333b1b6e62 100644
--- a/Source/core/paint/FloatClipRecorder.cpp
+++ b/Source/core/paint/FloatClipRecorder.cpp
@@ -17,13 +17,13 @@ FloatClipRecorder::FloatClipRecorder(GraphicsContext& context, const DisplayItem
     , m_client(client)
     , m_clipType(DisplayItem::paintPhaseToFloatClipType(paintPhase))
 {
+    FloatClipDisplayItem clipDisplayItem(m_client, m_clipType, clipRect);
     if (RuntimeEnabledFeatures::slimmingPaintEnabled()) {
         ASSERT(m_context.displayItemList());
         if (m_context.displayItemList()->displayItemConstructionIsDisabled())
             return;
-        m_context.displayItemList()->add(FloatClipDisplayItem::create(m_client, m_clipType, clipRect));
+        m_context.displayItemList()->add(clipDisplayItem);
     } else {
-        FloatClipDisplayItem clipDisplayItem(m_client, m_clipType, clipRect);
         clipDisplayItem.replay(m_context);
     }
 }
@@ -31,13 +31,13 @@ FloatClipRecorder::FloatClipRecorder(GraphicsContext& context, const DisplayItem
 FloatClipRecorder::~FloatClipRecorder()
 {
     DisplayItem::Type endType = DisplayItem::floatClipTypeToEndFloatClipType(m_clipType);
+    EndFloatClipDisplayItem endClipDisplayItem(m_client, endType);
     if (RuntimeEnabledFeatures::slimmingPaintEnabled()) {
         ASSERT(m_context.displayItemList());
         if (m_context.displayItemList()->displayItemConstructionIsDisabled())
             return;
-        m_context.displayItemList()->add(EndFloatClipDisplayItem::create(m_client, endType));
+        m_context.displayItemList()->add(endClipDisplayItem);
     } else {
-        EndFloatClipDisplayItem endClipDisplayItem(m_client, endType);
         endClipDisplayItem.replay(m_context);
     }
 }