Make operator == parameter non-nullable (#38663)

lib/web_ui/lib/src/engine/canvaskit/noto_font.dart

diff --git a/lib/web_ui/lib/src/engine/canvaskit/noto_font.dart b/lib/web_ui/lib/src/engine/canvaskit/noto_font.dart
index ad5b43e..25f52a7 100644
--- a/lib/web_ui/lib/src/engine/canvaskit/noto_font.dart
+++ b/lib/web_ui/lib/src/engine/canvaskit/noto_font.dart
@@ -65,7 +65,7 @@
   }
 
   @override
-  bool operator ==(dynamic other) {
+  bool operator ==(Object other) {
     if (other is! CodeunitRange) {
       return false;
     }