Use SVGLength-references in the SVGLengthContext API

Source/core/layout/svg/LayoutSVGResourcePattern.cpp

 /*
  * Copyright (C) 2006 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) Research In Motion Limited 2010. All rights reserved.
  * Copyright 2014 The Chromium Authors. 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
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 75 matching lines @@
 
     // An empty viewBox disables rendering.
     if (attributes.hasViewBox() && attributes.viewBox().isEmpty())
         return nullptr;
 
     ASSERT(element());
     // Compute tile metrics.
     FloatRect clientBoundingBox = object.objectBoundingBox();
     FloatRect tileBounds = SVGLengthContext::resolveRectangle(element(),
         attributes.patternUnits(), clientBoundingBox,
-        attributes.x(), attributes.y(), attributes.width(), attributes.height());
+        *attributes.x(), *attributes.y(), *attributes.width(), *attributes.height());
     if (tileBounds.isEmpty())
         return nullptr;
 
     AffineTransform tileTransform;
     if (attributes.hasViewBox()) {
         if (attributes.viewBox().isEmpty())
             return nullptr;
         tileTransform = SVGFitToViewBox::viewBoxToViewTransform(attributes.viewBox(),
             attributes.preserveAspectRatio(), tileBounds.width(), tileBounds.height());
     } else {
@@ skipping 78 matching lines @@
         for (LayoutObject* child = patternRenderer->firstChild(); child; child = child->nextSibling())
             SVGPaintContext::paintSubtree(&recordingContext, child);
     }
 
     if (displayItemList)
         displayItemList->replay(&recordingContext);
     return recordingContext.endRecording();
 }
 
 }