Make RenderObject::style() return a const object

Source/core/svg/SVGStopElement.cpp

Index: Source/core/svg/SVGStopElement.cpp
diff --git a/Source/core/svg/SVGStopElement.cpp b/Source/core/svg/SVGStopElement.cpp
index 30d7abfc7dc88145876ee6e944622a9d5a73cc0c..aca2be0861b5fdd4e84b8a1b2814ebdc2270e83c 100644
--- a/Source/core/svg/SVGStopElement.cpp
+++ b/Source/core/svg/SVGStopElement.cpp
@@ -58,7 +58,7 @@ void SVGStopElement::svgAttributeChanged(const QualifiedName& attrName)
     SVGElement::svgAttributeChanged(attrName);
 }
 
-RenderObject* SVGStopElement::createRenderer(RenderStyle*)
+RenderObject* SVGStopElement::createRenderer(const RenderStyle*)
 {
     return new RenderSVGGradientStop(this);
 }
@@ -70,7 +70,7 @@ bool SVGStopElement::rendererIsNeeded(const RenderStyle&)
 
 Color SVGStopElement::stopColorIncludingOpacity() const
 {
-    RenderStyle* style = renderer() ? renderer()->style() : 0;
+    const RenderStyle* style = renderer() ? renderer()->style() : 0;
     // FIXME: This check for null style exists to address Bug WK 90814, a rare crash condition in
     // which the renderer or style is null. This entire class is scheduled for removal (Bug WK 86941)
     // and we will tolerate this null check until then.