Hoist "layout size changed" check out of SVGLayoutSupport::layoutChildren

third_party/WebKit/Source/core/layout/svg/LayoutSVGContainer.cpp

 /*
  * Copyright (C) 2004, 2005, 2007 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2007, 2008 Rob Buis <buis@kde.org>
  * Copyright (C) 2007 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2009 Google, Inc.  All rights reserved.
  * Copyright (C) 2009 Dirk Schulze <krit@webkit.org>
  *
  * 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
@@ skipping 43 matching lines @@
     calcViewport();
 
     // Allow LayoutSVGTransformableContainer to update its transform.
     bool updatedTransform = calculateLocalTransform();
 
     // LayoutSVGViewportContainer needs to set the 'layout size changed' flag.
     determineIfLayoutSizeChanged();
 
     bool transformChanged = SVGLayoutSupport::transformToRootChanged(this);
 
+    // When hasRelativeLengths() is false, no descendants have relative lengths
+    // (hence no one is interested in viewport size changes).
+    bool layoutSizeChanged = element()->hasRelativeLengths()
+        && SVGLayoutSupport::layoutSizeOfNearestViewportChanged(this);
+
     // If any of this container's children need to be laid out, and a filter is
     // applied to the container, we need to issue paint invalidations for all
     // the descendants.
     bool forceLayoutOfChildren = selfNeedsLayout()
         || (normalChildNeedsLayout() && SVGLayoutSupport::hasFilterResource(*this));
-    SVGLayoutSupport::layoutChildren(this, forceLayoutOfChildren, transformChanged);
+    SVGLayoutSupport::layoutChildren(this, forceLayoutOfChildren, transformChanged, layoutSizeChanged);
 
     // Invalidate all resources of this client if our layout changed.
     if (everHadLayout() && needsLayout())
         SVGResourcesCache::clientLayoutChanged(this);
 
     if (m_needsBoundariesUpdate || updatedTransform) {
         updateCachedBoundaries();
         m_needsBoundariesUpdate = false;
 
         // If our bounds changed, notify the parents.
@@ skipping 113 matching lines @@
             updateHitTestResult(result, localLayoutPoint);
             if (result.addNodeToListBasedTestResult(element(), localLayoutPoint) == StopHitTesting)
                 return true;
         }
     }
     // 16.4: "If there are no graphics elements whose relevant graphics content is under the pointer (i.e., there is no target element), the event is not dispatched."
     return false;
 }
 
 } // namespace blink