[S.P.] Don't draw frames of animated images that are offscreen

Source/core/layout/LayoutObject.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 864 matching lines @@
     // FIXME: |paintInvalidationContainer| should never be 0. See crbug.com/363699.
     void invalidatePaintUsingContainer(const LayoutBoxModelObject* paintInvalidationContainer, const LayoutRect&, PaintInvalidationReason) const;
 
     // Invalidate the paint of a specific subrectangle within a given object. The rect |r| is in the object's coordinate space.
     void invalidatePaintRectangle(const LayoutRect&) const;
     void invalidatePaintRectangleNotInvalidatingDisplayItemClients(const LayoutRect& r) const { invalidatePaintRectangleInternal(r); }
 
     void invalidateSelectionIfNeeded(const LayoutBoxModelObject&, PaintInvalidationReason);
 
     // Walk the tree after layout issuing paint invalidations for renderers that have changed or moved, updating bounds that have changed, and clearing paint invalidation state.
-    virtual void invalidateTreeIfNeeded(const PaintInvalidationState&);
+    virtual void invalidateTreeIfNeeded(PaintInvalidationState&);
 
     virtual void invalidatePaintForOverflow();
     void invalidatePaintForOverflowIfNeeded();
 
     void invalidatePaintIncludingNonCompositingDescendants();
 
     // Returns the rect that should have paint invalidated whenever this object changes. The rect is in the view's
     // coordinate space. This method deals with outlines and overflow.
     virtual LayoutRect absoluteClippedOverflowRect() const;
     virtual LayoutRect clippedOverflowRectForPaintInvalidation(const LayoutBoxModelObject* paintInvalidationContainer, const PaintInvalidationState* = 0) const;
@@ skipping 310 matching lines @@
 
     virtual bool hasNonCompositedScrollbars() const { return false; }
 
 #if ENABLE(ASSERT)
     virtual bool paintInvalidationStateIsDirty() const
     {
         return neededLayoutBecauseOfChildren() || shouldCheckForPaintInvalidationRegardlessOfPaintInvalidationState();
     }
 #endif
 
-    virtual void invalidatePaintOfSubtreesIfNeeded(const PaintInvalidationState& childPaintInvalidationState);
-    virtual PaintInvalidationReason invalidatePaintIfNeeded(const PaintInvalidationState&, const LayoutBoxModelObject& paintInvalidationContainer);
+    virtual void invalidatePaintOfSubtreesIfNeeded(PaintInvalidationState& childPaintInvalidationState);
+    virtual PaintInvalidationReason invalidatePaintIfNeeded(PaintInvalidationState&, const LayoutBoxModelObject& paintInvalidationContainer);
 
     // When this object is invalidated for paint, this method is called to invalidate any DisplayItemClients
     // owned by this object, including the object itself, LayoutText/LayoutInline line boxes, etc.,
     // not including children which will be invalidated normally during invalidateTreeIfNeeded() and
     // parts which are invalidated separately (e.g. scrollbars).
     virtual void invalidateDisplayItemClients(const LayoutBoxModelObject& paintInvalidationContainer) const;
 
 private:
     void setLayoutDidGetCalledSinceLastFrame()
     {
@@ skipping 433 matching lines @@
 void showTree(const blink::LayoutObject*);
 void showLineTree(const blink::LayoutObject*);
 void showLayoutTree(const blink::LayoutObject* object1);
 // We don't make object2 an optional parameter so that showLayoutTree
 // can be called from gdb easily.
 void showLayoutTree(const blink::LayoutObject* object1, const blink::LayoutObject* object2);
 
 #endif
 
 #endif // LayoutObject_h