dart2js: don't emit unneeded native info.

tests/lib/typed_data/native_interceptor_with_method_to_intercept_test.dart

Index: tests/lib/typed_data/native_interceptor_with_method_to_intercept_test.dart
diff --git a/tests/isolate/issue_21398_child_isolate1.dart b/tests/lib/typed_data/native_interceptor_with_method_to_intercept_test.dart
similarity index 60%
copy from tests/isolate/issue_21398_child_isolate1.dart
copy to tests/lib/typed_data/native_interceptor_with_method_to_intercept_test.dart
index 1a720bd499c03102608f99aec1bc8e6aaf631101..aadb08f6e11db9fae35a34b38121e31cf2ae3b8b 100644
--- a/tests/isolate/issue_21398_child_isolate1.dart
+++ b/tests/lib/typed_data/native_interceptor_with_method_to_intercept_test.dart
@@ -2,11 +2,18 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import 'dart:isolate';
 import "package:expect/expect.dart";
+import 'dart:typed_data';
 
-main(List<String> args, message) {
-  var sendPort1 = args[0] as SendPort;
-  var sendPort2 = args[1] as SendPort;
-  sendPort2.send(sendPort1);
+class A {}
+
+confuse(x) {

[floitsch, 2015/02/26 18:12:12]

Use the Expect annotations instead.

+  return x;
+  return x;
+}
+
+main() {
+  confuse(new A());
+  confuse(new ByteData(1)).elementSizeInBytes;

[floitsch, 2015/02/26 18:12:12]

What does this unit-test test?

I would expect this to be completely unchanged by your patch. Did it fail
before?

[floitsch, 2015/02/26 18:12:12]

Check that things are doing the right thing.

[zarah, 2015/02/27 09:03:48]

It did not fail before, it was meant to illustrate the difference between the
two cases.

 }
+