[SPv2] Stop recording paired display items (except for subsequence markers)

third_party/WebKit/Source/platform/graphics/compositing/PaintChunksToCcLayer.cpp

 // Copyright 2017 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 "platform/graphics/compositing/PaintChunksToCcLayer.h"
 
 #include "cc/paint/compositing_display_item.h"
 #include "cc/paint/display_item_list.h"
 #include "cc/paint/drawing_display_item.h"
 #include "cc/paint/filter_display_item.h"
@@ skipping 163 matching lines @@
         ccList->CreateAndAppendPairedEndItem<cc::EndFilterDisplayItem>();
         ccList->CreateAndAppendPairedEndItem<cc::EndCompositingDisplayItem>();
         break;
     }
   }
 }
 
 static gfx::Rect largeRect(-200000, -200000, 400000, 400000);
 static void appendDisplayItemToCcDisplayItemList(const DisplayItem& displayItem,
                                                  cc::DisplayItemList* list) {
+  DCHECK(DisplayItem::isDrawingType(displayItem.getType()) ||
+         displayItem.getType() == DisplayItem::kSubsequence ||
+         displayItem.getType() == DisplayItem::kEndSubsequence);
   if (DisplayItem::isDrawingType(displayItem.getType())) {
     sk_sp<const PaintRecord> record =
         static_cast<const DrawingDisplayItem&>(displayItem).GetPaintRecord();
     if (!record)
       return;
     // In theory we would pass the bounds of the record, previously done as:
     // gfx::Rect bounds = gfx::SkIRectToRect(record->cullRect().roundOut());
     // or use the visual rect directly. However, clip content layers attempt
     // to raster in a different space than that of the visual rects. We'll be
     // reworking visual rects further for SPv2, so for now we just pass a
@@ skipping 41 matching lines @@
     recordPairedEndDisplayItems(endDisplayItems, ccList.get());
   }
 
   ccList->CreateAndAppendPairedEndItem<cc::EndTransformDisplayItem>();
 
   ccList->Finalize();
   return ccList;
 }
 
 }  // namespace blink