[WIP] do something :-)

Source/core/layout/LayoutObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 70 matching lines @@
 #include "core/style/ShadowList.h"
 #include "platform/JSONValues.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/TraceEvent.h"
 #include "platform/TracedValue.h"
 #include "platform/geometry/TransformState.h"
 #include "platform/graphics/GraphicsContext.h"
 #include "platform/graphics/paint/DisplayItemList.h"
 #include "wtf/Partitions.h"
 #include "wtf/RefCountedLeakCounter.h"
+#include "wtf/SizeAssertions.h"
 #include "wtf/text/StringBuilder.h"
 #include "wtf/text/WTFString.h"
 #include <algorithm>
 #ifndef NDEBUG
 #include <stdio.h>
 #endif
 
 namespace blink {
 
 namespace {
 
 static bool gModifyLayoutTreeStructureAnyState = false;
 
 static bool gDisablePaintInvalidationStateAsserts = false;
 
 } // namespace
 
 using namespace HTMLNames;
 
+ASSERT_SIZE(LayoutObject, 56, 80);
+
 const LayoutUnit& caretWidth()
 {
     static LayoutUnit gCaretWidth(1);
     return gCaretWidth;
 }
 
 #if ENABLE(ASSERT)
-
 LayoutObject::SetLayoutNeededForbiddenScope::SetLayoutNeededForbiddenScope(LayoutObject& layoutObject)
     : m_layoutObject(layoutObject)
     , m_preexistingForbidden(m_layoutObject.isSetNeedsLayoutForbidden())
 {
     m_layoutObject.setNeedsLayoutIsForbidden(true);
 }
 
 LayoutObject::SetLayoutNeededForbiddenScope::~SetLayoutNeededForbiddenScope()
 {
     m_layoutObject.setNeedsLayoutIsForbidden(m_preexistingForbidden);
 }
 #endif
 
-struct SameSizeAsLayoutObject {
-    virtual ~SameSizeAsLayoutObject() { } // Allocate vtable pointer.
-    void* pointers[5];
-#if ENABLE(ASSERT)
-    unsigned m_debugBitfields : 2;
-#endif
-    unsigned m_bitfields;
-    unsigned m_bitfields2;
-    LayoutRect rect; // Stores the previous paint invalidation rect.
-    LayoutPoint position; // Stores the previous position from the paint invalidation container.
-};
-
-static_assert(sizeof(LayoutObject) == sizeof(SameSizeAsLayoutObject), "LayoutObject should stay small");
-
 bool LayoutObject::s_affectsParentBlock = false;
 
 typedef HashMap<const LayoutObject*, LayoutRect> SelectionPaintInvalidationMap;
 static SelectionPaintInvalidationMap* selectionPaintInvalidationMap = nullptr;
 
 void* LayoutObject::operator new(size_t sz)
 {
     ASSERT(isMainThread());
     return partitionAlloc(WTF::Partitions::layoutPartition(), sz);
 }
@@ skipping 3249 matching lines @@
         const blink::LayoutObject* root = object1;
         while (root->parent())
             root = root->parent();
         root->showLayoutTreeAndMark(object1, "*", object2, "-", 0);
     } else {
         fprintf(stderr, "Cannot showLayoutTree. Root is (nil)\n");
     }
 }
 
 #endif