Reset m_didTransformToRootUpdate flag during invalidationTreeIfNeeded

Source/core/rendering/svg/RenderSVGViewportContainer.cpp

 /*
  * Copyright (C) 2004, 2005, 2007 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2007 Rob Buis <buis@kde.org>
  * Copyright (C) 2007 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2009 Google, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 56 matching lines @@
     m_viewport = FloatRect(svg->x()->currentValue()->value(lengthContext), svg->y()->currentValue()->value(lengthContext), svg->width()->currentValue()->value(lengthContext), svg->height()->currentValue()->value(lengthContext));
 
     if (oldViewport != m_viewport) {
         setNeedsBoundariesUpdate();
         setNeedsTransformUpdate();
     }
 }
 
 bool RenderSVGViewportContainer::calculateLocalTransform()
 {
-    m_didTransformToRootUpdate = m_needsTransformUpdate || SVGRenderSupport::transformToRootChanged(parent());
+    if (m_needsTransformUpdate || SVGRenderSupport::transformToRootChanged(parent()))
+        m_didTransformToRootUpdate = true;
+
     if (!m_needsTransformUpdate)
         return false;
 
     m_localToParentTransform = AffineTransform::translation(m_viewport.x(), m_viewport.y()) * viewportTransform();
     m_needsTransformUpdate = false;
     return true;
 }
 
 AffineTransform RenderSVGViewportContainer::viewportTransform() const
 {
@@ skipping 18 matching lines @@
 void RenderSVGViewportContainer::paint(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
 {
     ASSERT(element());
     // An empty viewBox disables rendering.
     if (isSVGSVGElement(*element()) && toSVGSVGElement(*element()).hasEmptyViewBox())
         return;
 
     RenderSVGContainer::paint(paintInfo, paintOffset);
 }
 
+void RenderSVGViewportContainer::clearPaintInvalidationState()
+{
+    RenderSVGContainer::clearPaintInvalidationState();
+
+    ASSERT(!m_needsTransformUpdate);
+    m_didTransformToRootUpdate = false;
 }
+
+}