fix #27631, get/set methods no longer shadow index operator

pkg/dev_compiler/test/codegen_expected/BenchmarkBase.js

Index: pkg/dev_compiler/test/codegen_expected/BenchmarkBase.js
diff --git a/pkg/dev_compiler/test/codegen_expected/BenchmarkBase.js b/pkg/dev_compiler/test/codegen_expected/BenchmarkBase.js
index 7535ac0f06240318373563f3f8f1b0b9c8c3d4ff..48a5eb6bd24cae5e28431c3598de19957965a4e1 100644
--- a/pkg/dev_compiler/test/codegen_expected/BenchmarkBase.js
+++ b/pkg/dev_compiler/test/codegen_expected/BenchmarkBase.js
@@ -16,7 +16,7 @@ define(['dart_sdk'], function(dart_sdk) {
         dart.throw(dart.str`Lists have different lengths: ${expected[dartx.length]} vs ${actual[dartx.length]}`);
       }
       for (let i = 0; i < dart.notNull(actual[dartx.length]); i++) {
-        BenchmarkBase$.Expect.equals(expected[dartx.get](i), actual[dartx.get](i));
+        BenchmarkBase$.Expect.equals(expected[dartx._get](i), actual[dartx._get](i));
       }
     }
     fail(message) {