Cleanup DisplayItemList::processNewItem to take a reference

Source/platform/graphics/paint/DisplayItemList.h

 // Copyright 2014 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.
 
 #ifndef DisplayItemList_h
 #define DisplayItemList_h
 
 #include "platform/PlatformExport.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/geometry/LayoutPoint.h"
@@ skipping 52 matching lines @@
     // These methods are called during painting.
     template <typename DisplayItemClass, typename... Args>
     DisplayItemClass& createAndAppend(Args&&... args)
     {
         static_assert(WTF::IsSubclass<DisplayItemClass, DisplayItem>::value,
             "Can only createAndAppend subclasses of DisplayItem.");
         static_assert(sizeof(DisplayItemClass) <= kMaximumDisplayItemSize,
             "DisplayItem subclass is larger than kMaximumDisplayItemSize.");
 
         DisplayItemClass& displayItem = m_newDisplayItems.allocateAndConstruct<DisplayItemClass>(WTF::forward<Args>(args)...);
-        processNewItem(&displayItem);
+        processNewItem(displayItem);
         return displayItem;
     }
 
     // Scopes must be used to avoid duplicated display item ids when we paint some object
     // multiple times and generate multiple display items with the same type.
     // We don't cache display items added in scopes.
     void beginScope();
     void endScope();
 
     // True if the last display item is a begin that doesn't draw content.
@@ skipping 66 matching lines @@
         , m_nextScope(1) { }
 
 private:
     friend class DisplayItemListTest;
     friend class DisplayItemListPaintTest;
     friend class DisplayItemListPaintTestForSlimmingPaintV2;
     friend class LayoutObjectDrawingRecorderTest;
     friend class LayoutObjectDrawingRecorderTestForSlimmingPaintV2;
 
     // Set new item state (scopes, cache skipping, etc) for a new item.
-    // TODO(pdr): This only passes a pointer to make the patch easier to review. Change to a reference.
-    void processNewItem(DisplayItem*);
+    void processNewItem(DisplayItem&);
 
     void updateValidlyCachedClientsIfNeeded() const;
 
     // Update the recorded paint offsets to remove any items that no longer have
     // corresponding cached display items.
     // TODO(pdr): Remove this once the paint offset cache is on LayoutObject.
     void removeUnneededPaintOffsetEntries();
 
 #ifndef NDEBUG
     WTF::String displayItemsAsDebugString(const DisplayItems&) const;
@@ skipping 60 matching lines @@
     // the duplicated ids are from.
     DisplayItemIndicesByClientMap m_newDisplayItemIndicesByClient;
 #endif
 
     OwnPtr<Vector<String>> m_trackedPaintInvalidationObjects;
 };
 
 } // namespace blink
 
 #endif // DisplayItemList_h