Statistics of LayoutBox rare data reasons

third_party/WebKit/Source/platform/graphics/paint/DisplayItemClient.h

 // Copyright 2015 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 DisplayItemClient_h
 #define DisplayItemClient_h
 
 #include "platform/PlatformExport.h"
 #include "platform/geometry/LayoutRect.h"
 #include "platform/graphics/PaintInvalidationReason.h"
 #include "wtf/Assertions.h"
 #include "wtf/text/WTFString.h"
 
 #define CHECK_DISPLAY_ITEM_CLIENT_ALIVENESS DCHECK_IS_ON()
 
 namespace blink {
 
 // The class for objects that can be associated with display items. A
 // DisplayItemClient object should live at least longer than the document cycle
 // in which its display items are created during painting. After the document
 // cycle, a pointer/reference to DisplayItemClient should be no longer
 // dereferenced unless we can make sure the client is still valid.
+
 class PLATFORM_EXPORT DisplayItemClient {
  public:
 #if CHECK_DISPLAY_ITEM_CLIENT_ALIVENESS
   DisplayItemClient();
   virtual ~DisplayItemClient();
 
   // Tests if this DisplayItemClient object has been created and has not been
   // deleted yet.
   bool isAlive() const;
 
@@ skipping 148 matching lines @@
   return &client1 == &client2;
 }
 inline bool operator!=(const DisplayItemClient& client1,
                        const DisplayItemClient& client2) {
   return &client1 != &client2;
 }
 
 }  // namespace blink
 
 #endif  // DisplayItemClient_h