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

Source/core/paint/SVGClipPainter.cpp

Index: Source/core/paint/SVGClipPainter.cpp
diff --git a/Source/core/paint/SVGClipPainter.cpp b/Source/core/paint/SVGClipPainter.cpp
index 4d49205577d979988048f3af89f665e6d7e61980..410153c8aa63076998804d8ec01f4e90b3bf5b2a 100644
--- a/Source/core/paint/SVGClipPainter.cpp
+++ b/Source/core/paint/SVGClipPainter.cpp
@@ -97,17 +97,18 @@ bool SVGClipPainter::applyClippingToContext(const LayoutObject& target, const Fl
 void SVGClipPainter::postApplyStatefulResource(const LayoutObject& target, GraphicsContext* context, ClipperState& clipperState)
 {
     switch (clipperState) {
-    case ClipperAppliedPath:
+    case ClipperAppliedPath: {
         // Path-only clipping, no layers to restore but we need to emit an end to the clip path display item.
+        EndClipPathDisplayItem endClipPathDisplayItem(target);
         if (RuntimeEnabledFeatures::slimmingPaintEnabled()) {
             if (context->displayItemList()->displayItemConstructionIsDisabled())
                 return;
-            context->displayItemList()->add(EndClipPathDisplayItem::create(target));
+            context->displayItemList()->add(endClipPathDisplayItem);
         } else {
-            EndClipPathDisplayItem endClipPathDisplayItem(target);
             endClipPathDisplayItem.replay(*context);
         }
         break;
+    }
     case ClipperAppliedMask:
         // Transfer content -> clip mask (SrcIn)
         CompositingRecorder::endCompositing(*context, target);
@@ -128,13 +129,13 @@ void SVGClipPainter::drawClipMaskContent(GraphicsContext* context, const LayoutO
     RefPtr<const SkPicture> clipContentPicture = m_clip.createContentPicture(contentTransformation, targetBoundingBox, context);
 
     TransformRecorder recorder(*context, layoutObject, contentTransformation);
+    DrawingDisplayItem clipPicture(layoutObject, DisplayItem::SVGClip, clipContentPicture);
     if (RuntimeEnabledFeatures::slimmingPaintEnabled()) {
         ASSERT(context->displayItemList());
         if (context->displayItemList()->displayItemConstructionIsDisabled())
             return;
-        context->displayItemList()->add(DrawingDisplayItem::create(layoutObject, DisplayItem::SVGClip, clipContentPicture));
+        context->displayItemList()->add(clipPicture);
     } else {
-        DrawingDisplayItem clipPicture(layoutObject, DisplayItem::SVGClip, clipContentPicture);
         clipPicture.replay(*context);
     }
 }