dart2js: Remove isD8 and isJsShell functions.

tests/compiler/dart2js_native/only_pass_on_jsshell_test.dart

Index: tests/compiler/dart2js_native/only_pass_on_jsshell_test.dart
diff --git a/tests/compiler/dart2js_native/only_pass_on_jsshell_test.dart b/tests/compiler/dart2js_native/only_pass_on_jsshell_test.dart
deleted file mode 100644
index 17fce76f02882c3c64161398f14eb702299393ef..0000000000000000000000000000000000000000
--- a/tests/compiler/dart2js_native/only_pass_on_jsshell_test.dart
+++ /dev/null
@@ -1,12 +0,0 @@
-// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
-// 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 'package:expect/expect.dart';
-
-import 'dart:_js_helper' show Primitives;
-
-main() {
-  Expect.isFalse(Primitives.isD8);
-  Expect.isTrue(Primitives.isJsshell);
-}