Make CursorPainter constructor named

lib/src/widgets/cursor.dart

@@ -228,13 +228,13 @@ class CursorCont extends ChangeNotifier {
 
 /// Paints the editing cursor.
 class CursorPainter {
-  CursorPainter(
+  CursorPainter({
-    this.editable,
+    required this.editable,
-    this.style,
+    required this.style,
-    this.prototype,
+    required this.prototype,
-    this.color,
+    required this.color,
-    this.devicePixelRatio,
+    required this.devicePixelRatio,
-  );
+  });
 
   final RenderContentProxyBox? editable;
   final CursorStyle style;

lib/src/widgets/text_line.dart

@@ -815,11 +815,11 @@ class RenderEditableTextLine extends RenderEditableBox {
   }
 
   CursorPainter get _cursorPainter => CursorPainter(
-        _body,
+        editable: _body,
-        cursorCont.style,
+        style: cursorCont.style,
-        _caretPrototype!,
+        prototype: _caretPrototype!,
-        cursorCont.color.value,
+        color: cursorCont.color.value,
-        devicePixelRatio,
+        devicePixelRatio: devicePixelRatio,
       );
 
   @override