Introduce DEFINE_RENDER_OBJECT_TYPE_CASTS to replace manual toRenderFoo, and use it

Source/core/rendering/RenderTextControlSingleLine.h

Index: Source/core/rendering/RenderTextControlSingleLine.h
diff --git a/Source/core/rendering/RenderTextControlSingleLine.h b/Source/core/rendering/RenderTextControlSingleLine.h
index 3e0ba87bb0f9b2dea95272ae4a4d86947249cf88..a752e90c4358e4e2c5766210cc0a098416365fbd 100644
--- a/Source/core/rendering/RenderTextControlSingleLine.h
+++ b/Source/core/rendering/RenderTextControlSingleLine.h
@@ -84,14 +84,7 @@ private:
     LayoutUnit m_desiredInnerTextLogicalHeight;
 };
 
-inline RenderTextControlSingleLine* toRenderTextControlSingleLine(RenderObject* object)
-{
-    ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isTextField());
-    return static_cast<RenderTextControlSingleLine*>(object);
-}
-
-// This will catch anyone doing an unnecessary cast.
-void toRenderTextControlSingleLine(const RenderTextControlSingleLine*);
+DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderTextControlSingleLine, isTextField());
 
 // ----------------------------