Introduce DEFINE_RENDER_OBJECT_TYPE_CASTS to replace manual toRenderFoo, and use it

Source/core/rendering/RenderListBox.h

Index: Source/core/rendering/RenderListBox.h
diff --git a/Source/core/rendering/RenderListBox.h b/Source/core/rendering/RenderListBox.h
index 9c4eceba769af5ec6dc1f7667d851304f635bb82..fb10cebc190e42235ee1271f7f013bf1ff88d27a 100644
--- a/Source/core/rendering/RenderListBox.h
+++ b/Source/core/rendering/RenderListBox.h
@@ -160,14 +160,7 @@ private:
     RefPtr<Scrollbar> m_vBar;
 };
 
-inline RenderListBox* toRenderListBox(RenderObject* object)
-{
-    ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isListBox());
-    return static_cast<RenderListBox*>(object);
-}
-
-// This will catch anyone doing an unnecessary cast.
-void toRenderListBox(const RenderListBox*);
+DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderListBox, isListBox());
 
 } // namepace WebCore