Introduce DEFINE_RENDER_OBJECT_TYPE_CASTS to replace manual toRenderFoo, and use it

Source/core/rendering/RenderImage.h

Index: Source/core/rendering/RenderImage.h
diff --git a/Source/core/rendering/RenderImage.h b/Source/core/rendering/RenderImage.h
index bdd55666926e613e70c6e9213c79ce5e75683681..17df74263ac5d603f2015086599950ee04b29f6a 100644
--- a/Source/core/rendering/RenderImage.h
+++ b/Source/core/rendering/RenderImage.h
@@ -120,20 +120,7 @@ private:
     friend class RenderImageScaleObserver;
 };
 
-inline RenderImage* toRenderImage(RenderObject* object)
-{
-    ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isRenderImage());
-    return static_cast<RenderImage*>(object);
-}
-
-inline const RenderImage* toRenderImage(const RenderObject* object)
-{
-    ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isRenderImage());
-    return static_cast<const RenderImage*>(object);
-}
-
-// This will catch anyone doing an unnecessary cast.
-void toRenderImage(const RenderImage*);
+DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderImage, isRenderImage());
 
 } // namespace WebCore