Reland of Client side display item cache flag

third_party/WebKit/Source/platform/graphics/paint/DisplayItem.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 DisplayItem_h
 #define DisplayItem_h
 
 #include "platform/PlatformExport.h"
 #include "platform/graphics/ContiguousContainer.h"
 #include "platform/graphics/paint/DisplayItemClient.h"
@@ skipping 312 matching lines @@
     DEFINE_PAIRED_CATEGORY_METHODS(Transform3D, transform3D)
 
     static bool isCachedType(Type type) { return isCachedDrawingType(type) || type == CachedSubsequence; }
     bool isCached() const { return isCachedType(m_type); }
     static bool isCacheableType(Type type) { return isDrawingType(type) || type == Subsequence; }
     bool isCacheable() const { return !skippedCache() && isCacheableType(m_type); }
 
     virtual bool isBegin() const { return false; }
     virtual bool isEnd() const { return false; }
 
-#if ENABLE(ASSERT)
+#if DCHECK_IS_ON()
     virtual bool isEndAndPairedWith(DisplayItem::Type otherType) const { return false; }
     virtual bool equals(const DisplayItem& other) const
     {
         return m_client == other.m_client
             && m_scope == other.m_scope
             && m_type == other.m_type
             && m_derivedSize == other.m_derivedSize
             && m_skippedCache == other.m_skippedCache;
     }
+#endif
 
     // True if the client is non-null. Because m_client is const, this should
     // never be false except when we explicitly create a tombstone/"dead display
     // item" as part of moving an item from one list to another (see:
     // DisplayItemList::appendByMoving).
     bool hasValidClient() const { return m_client; }
-#endif
 
     virtual bool drawsContent() const { return false; }
 
 #ifndef NDEBUG
     static WTF::String typeAsDebugString(DisplayItem::Type);
     const WTF::String clientDebugString() const { return m_clientDebugString; }
     void setClientDebugString(const WTF::String& s) { m_clientDebugString = s; }
     WTF::String asDebugString() const;
     virtual void dumpPropertiesAsDebugString(WTF::StringBuilder&) const;
 #endif
@@ skipping 40 matching lines @@
     bool isEndAndPairedWith(DisplayItem::Type otherType) const override = 0;
 #endif
 
 private:
     bool isEnd() const final { return true; }
 };
 
 } // namespace blink
 
 #endif // DisplayItem_h