Create binstubs for executables when activating a package.

sdk/lib/_internal/pub/test/global/binstubs/explicit_executables_test.dart

+// Copyright (c) 2014, 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("only creates binstubs for the listed executables", () {
+    d.dir("foo", [
+      d.pubspec({
+        "name": "foo",
+        "executables": {
+          "one": "script",
+          "two": "script",
+          "three": "script"
+        }
+      }),
+      d.dir("bin", [
+        d.file("script.dart", "main() => print('ok');")
+      ])
+    ]).create();
+
+    schedulePub(args: [
+      "global", "activate", "--source", "path", "../foo",
+      "-x", "one", "--executable", "three"
+    ], output: contains("Installed executables one and three."));
+
+    d.dir(cachePath, [
+      d.dir("bin", [
+        d.matcherFile("one", contains("pub global run foo:script")),
+        d.nothing("two"),
+        d.matcherFile("three", contains("pub global run foo:script"))
+      ])
+    ]).validate();
+  });
+}