Check in codegen test expectations.

test/codegen/expect/language/list_tracer_in_list_test.js

Index: test/codegen/expect/language/list_tracer_in_list_test.js
diff --git a/test/codegen/expect/language/list_tracer_in_list_test.js b/test/codegen/expect/language/list_tracer_in_list_test.js
new file mode 100644
index 0000000000000000000000000000000000000000..3ce5cd8ae06b8c621d47ffd264c287ffad6c102e
--- /dev/null
+++ b/test/codegen/expect/language/list_tracer_in_list_test.js
@@ -0,0 +1,22 @@
+dart_library.library('language/list_tracer_in_list_test', null, /* Imports */[
+  'dart_sdk'
+], function load__list_tracer_in_list_test(exports, dart_sdk) {
+  'use strict';
+  const core = dart_sdk.core;
+  const _interceptors = dart_sdk._interceptors;
+  const dart = dart_sdk.dart;
+  const dartx = dart_sdk.dartx;
+  const list_tracer_in_list_test = Object.create(null);
+  let JSArrayOfList = () => (JSArrayOfList = dart.constFn(_interceptors.JSArray$(core.List)))();
+  let VoidTodynamic = () => (VoidTodynamic = dart.constFn(dart.definiteFunctionType(dart.dynamic, [])))();
+  list_tracer_in_list_test.main = function() {
+    let a = JSArrayOfList().of([[]]);
+    a[dartx.get](0)[dartx.add](42);
+    if (a[dartx.get](0)[dartx.length] != 1) {
+      dart.throw('Test failed');
+    }
+  };
+  dart.fn(list_tracer_in_list_test.main, VoidTodynamic());
+  // Exports:
+  exports.list_tracer_in_list_test = list_tracer_in_list_test;
+});