[SVG] Transform animation leaves traces of text behind.

Source/core/rendering/PaintInfo.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 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 77 matching lines @@
     void applyTransform(const AffineTransform& localToAncestorTransform, bool identityStatusUnknown = true)
     {
         if (identityStatusUnknown && localToAncestorTransform.isIdentity())
             return;
 
         context->concatCTM(localToAncestorTransform);
 
         if (rect == infiniteRect())
             return;
 
-        rect = localToAncestorTransform.inverse().mapRect(rect);
+        if (localToAncestorTransform.isInvertible())
+            rect = localToAncestorTransform.inverse().mapRect(rect);
+        else
+            rect.setSize(IntSize(0, 0));
     }
 
     static IntRect infiniteRect() { return IntRect(LayoutRect::infiniteRect()); }
     const RenderLayerModelObject* paintContainer() const { return m_paintContainer; }
 
     ListHashSet<RenderInline*>* outlineObjects() { return m_outlineObjects; }
     void setOutlineObjects(ListHashSet<RenderInline*>* objects) { m_outlineObjects = objects; }
 
     // FIXME: Introduce setters/getters at some point. Requires a lot of changes throughout rendering/.
     GraphicsContext* context;
     IntRect rect;
     PaintPhase phase;
     PaintBehavior paintBehavior;
     RenderObject* paintingRoot; // used to draw just one element and its visual kids
     OverlapTestRequestMap* overlapTestRequests;
 
 private:
 
     const RenderLayerModelObject* m_paintContainer; // the layer object that originates the current painting
     ListHashSet<RenderInline*>* m_outlineObjects; // used to list outlines that should be painted by a block with inline children
 };
 
 } // namespace WebCore
 
 #endif // PaintInfo_h