Allow user to specify mode for pub build/serve.

sdk/lib/_internal/pub/test/build/minifies_js_by_default_test.dart

Index: sdk/lib/_internal/pub/test/build/minifies_js_by_default_test.dart
diff --git a/sdk/lib/_internal/pub/test/build/minifies_js_by_default_test.dart b/sdk/lib/_internal/pub/test/build/minifies_js_by_default_test.dart
deleted file mode 100644
index 73f58dd82c1d663f6020f6a99c343d7cef232ec2..0000000000000000000000000000000000000000
--- a/sdk/lib/_internal/pub/test/build/minifies_js_by_default_test.dart
+++ /dev/null
@@ -1,35 +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:scheduled_test/scheduled_test.dart';
-
-import '../descriptor.dart' as d;
-import '../test_pub.dart';
-
-main() {
-  initConfig();
-
-  integration("generates minified JavaScript", () {
-    // Dart2js can take a long time to compile dart code, so we increase the
-    // timeout to cope with that.
-    currentSchedule.timeout *= 3;
-
-    d.dir(appPath, [
-      d.appPubspec(),
-      d.dir('web', [
-        d.file('main.dart', 'void main() => print("hello");')
-      ])
-    ]).create();
-
-    schedulePub(args: ["build"],
-        output: new RegExp(r"Built 1 file!"),
-        exitCode: 0);
-
-    d.dir(appPath, [
-      d.dir('build', [
-        d.matcherFile('main.dart.js', isMinifiedDart2JSOutput)
-      ])
-    ]).validate();
-  });
-}