Use isSVG*Element() helpers more in SVG code (Part 1)

Source/core/svg/SVGFEDiffuseLightingElement.cpp

 /*
  * Copyright (C) 2005 Oliver Hunt <ojh16@student.canterbury.ac.nz>
  *
  * 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.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 84 matching lines @@
         ASSERT(renderer);
         ASSERT(renderer->style());
         return diffuseLighting->setLightingColor(renderer->style()->svgStyle()->lightingColor());
     }
     if (attrName == SVGNames::surfaceScaleAttr)
         return diffuseLighting->setSurfaceScale(m_surfaceScale->currentValue()->value());
     if (attrName == SVGNames::diffuseConstantAttr)
         return diffuseLighting->setDiffuseConstant(m_diffuseConstant->currentValue()->value());
 
     LightSource* lightSource = const_cast<LightSource*>(diffuseLighting->lightSource());
-    const SVGFELightElement* lightElement = SVGFELightElement::findLightElement(this);
+    const SVGFELightElement* lightElement = SVGFELightElement::findLightElement(*this);
     ASSERT(lightSource);
     ASSERT(lightElement);
 
     if (attrName == SVGNames::azimuthAttr)
         return lightSource->setAzimuth(lightElement->azimuth()->currentValue()->value());
     if (attrName == SVGNames::elevationAttr)
         return lightSource->setElevation(lightElement->elevation()->currentValue()->value());
     if (attrName == SVGNames::xAttr)
         return lightSource->setX(lightElement->x()->currentValue()->value());
     if (attrName == SVGNames::yAttr)
@@ skipping 35 matching lines @@
     if (attrName == SVGNames::inAttr) {
         invalidate();
         return;
     }
 
     ASSERT_NOT_REACHED();
 }
 
 void SVGFEDiffuseLightingElement::lightElementAttributeChanged(const SVGFELightElement* lightElement, const QualifiedName& attrName)
 {
-    if (SVGFELightElement::findLightElement(this) != lightElement)
+    if (SVGFELightElement::findLightElement(*this) != lightElement)
         return;
 
     // The light element has different attribute names.
     primitiveAttributeChanged(attrName);
 }
 
 PassRefPtr<FilterEffect> SVGFEDiffuseLightingElement::build(SVGFilterBuilder* filterBuilder, Filter* filter)
 {
     FilterEffect* input1 = filterBuilder->getEffectById(AtomicString(m_in1->currentValue()->value()));
 
     if (!input1)
         return nullptr;
 
-    RefPtr<LightSource> lightSource = SVGFELightElement::findLightSource(this);
+    RefPtr<LightSource> lightSource = SVGFELightElement::findLightSource(*this);
     if (!lightSource)
         return nullptr;
 
     RenderObject* renderer = this->renderer();
     if (!renderer)
         return nullptr;
 
     ASSERT(renderer->style());
     Color color = renderer->style()->svgStyle()->lightingColor();
 
     RefPtr<FilterEffect> effect = FEDiffuseLighting::create(filter, color, m_surfaceScale->currentValue()->value(), m_diffuseConstant->currentValue()->value(),
         kernelUnitLengthX()->currentValue()->value(), kernelUnitLengthY()->currentValue()->value(), lightSource.release());
     effect->inputEffects().append(input1);
     return effect.release();
 }
 
 }