Handle dynamic as bottom inside of function type reps

test/codegen/expect/sunflower/sunflower.js

Index: test/codegen/expect/sunflower/sunflower.js
diff --git a/test/codegen/expect/sunflower/sunflower.js b/test/codegen/expect/sunflower/sunflower.js
index aae61805bef4c1a541aa3c937abfc368ac0d3a01..fe4c3da20420d3a66e183dd76d24d39114886b25 100644
--- a/test/codegen/expect/sunflower/sunflower.js
+++ b/test/codegen/expect/sunflower/sunflower.js
@@ -37,7 +37,7 @@ dart_library.library('sunflower', null, /* Imports */[
     }
   });
   function main() {
-    exports.slider.addEventListener('change', dart.fn(e => draw(), dart.void, [core.Object]));
+    exports.slider.addEventListener('change', dart.fn(e => draw(), dart.void, [dart.dynamic]));
     draw();
   }
   dart.fn(main, dart.void, []);