Make DisplayItem::replay const.

third_party/WebKit/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/IntRect.h"
@@ skipping 220 matching lines @@
     void copyCachedSubsequence(DisplayItems::iterator& currentIt, DisplayItems& updatedList);
 
 #if ENABLE(ASSERT)
     // The following two methods are for checking under-invalidations
     // (when RuntimeEnabledFeatures::slimmingPaintUnderInvalidationCheckingEnabled).
     void checkUnderInvalidation(DisplayItems::iterator& newIt, DisplayItems::iterator& currentIt);
     void checkCachedDisplayItemIsUnchanged(const char* messagePrefix, const DisplayItem& newItem, const DisplayItem& oldItem);
     void checkNoRemainingCachedDisplayItems();
 #endif
 
-    void replay(GraphicsContext&);
+    void replay(GraphicsContext&) const;
 
     DisplayItems m_currentDisplayItems;
     DisplayItems m_newDisplayItems;
 
     // In Slimming Paint v2, paint properties (e.g. transform) useful for
     // compositing are stored in corresponding paint chunks instead of in the
     // display items.
     Vector<PaintChunk> m_currentPaintChunks;
     PaintChunker m_newPaintChunks;
 
@@ skipping 42 matching lines @@
     // the duplicated ids are from.
     DisplayItemIndicesByClientMap m_newDisplayItemIndicesByClient;
 #endif
 
     OwnPtr<Vector<String>> m_trackedPaintInvalidationObjects;
 };
 
 } // namespace blink
 
 #endif // DisplayItemList_h