[CSS Regions] Add new regionOversetChange event

Source/core/rendering/RenderNamedFlowThread.h

 /*
  * Copyright (C) 2012 Apple Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 69 matching lines @@
     void resetMarkForDestruction();
 
 private:
     RenderNamedFlowThread(PassRefPtr<NamedFlow>);
 
     virtual const char* renderName() const OVERRIDE;
     virtual bool isRenderNamedFlowThread() const OVERRIDE { return true; }
     virtual bool isChildAllowed(RenderObject*, RenderStyle*) const OVERRIDE;
 
     virtual void dispatchRegionLayoutUpdateEvent() OVERRIDE;
+    virtual void dispatchRegionOversetChangeEvent() OVERRIDE;
 
     bool dependsOn(RenderNamedFlowThread* otherRenderFlowThread) const;
     void addDependencyOnFlowThread(RenderNamedFlowThread*);
     void removeDependencyOnFlowThread(RenderNamedFlowThread*);
 
     void addRegionToNamedFlowThread(RenderRegion*);
 
     void checkInvalidRegions();
 
     bool canBeDestroyed() const { return m_invalidRegionList.isEmpty() && m_regionList.isEmpty() && m_contentNodes.isEmpty(); }
     void regionLayoutUpdateEventTimerFired(Timer<RenderNamedFlowThread>*);
+    void regionOversetChangeEventTimerFired(Timer<RenderNamedFlowThread>*);
     void clearContentNodes();
 
 private:
     // Observer flow threads have invalid regions that depend on the state of this thread
     // to re-validate their regions. Keeping a set of observer threads make it easy
     // to notify them when a region was removed from this flow.
     RenderNamedFlowThreadCountedSet m_observerThreadsSet;
 
     // Some threads need to have a complete layout before we layout this flow.
     // That's because they contain a RenderRegion that should display this thread. The set makes it
     // easy to sort the order of threads layout.
     RenderNamedFlowThreadCountedSet m_layoutBeforeThreadsSet;
 
     // Holds the sorted children of a named flow. This is the only way we can get the ordering right.
     typedef ListHashSet<RenderObject*> FlowThreadChildList;
     FlowThreadChildList m_flowThreadChildList;
 
     NamedFlowContentNodes m_contentNodes;
 
     RenderRegionList m_invalidRegionList;
 
     // The DOM Object that represents a named flow.
     RefPtr<NamedFlow> m_namedFlow;
 
     Timer<RenderNamedFlowThread> m_regionLayoutUpdateEventTimer;
+    Timer<RenderNamedFlowThread> m_regionOversetChangeEventTimer;
 };
 
 inline RenderNamedFlowThread* toRenderNamedFlowThread(RenderObject* object)
 {
     ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isRenderNamedFlowThread());
     return static_cast<RenderNamedFlowThread*>(object);
 }
 
 inline const RenderNamedFlowThread* toRenderNamedFlowThread(const RenderObject* object)
 {
     ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isRenderNamedFlowThread());
     return static_cast<const RenderNamedFlowThread*>(object);
 }
 
 // This will catch anyone doing an unnecessary cast.
 void toRenderNamedFlowThread(const RenderNamedFlowThread*);
 
 } // namespace WebCore
 
 #endif // RenderNamedFlowThread_h