Add an option to run skipped tests.

test/runner/expanded_reporter_test.dart

 // Copyright (c) 2015, 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.
 
 @TestOn("vm")
 
 import 'package:scheduled_test/descriptor.dart' as d;
 import 'package:scheduled_test/scheduled_stream.dart';
 import 'package:scheduled_test/scheduled_test.dart';
 
@@ skipping 241 matching lines @@
     });
 
     test("displays a skipped group", () {
       _expectReport("""
           group('skip', () {
             test('test 1', () {});
             test('test 2', () {});
             test('test 3', () {});
           }, skip: true);""",
           """
-          +0: skip
-          +0 ~1: All tests skipped.""");
+          +0: skip test 1
+          +0 ~1: skip test 2
+          +0 ~2: skip test 3
+          +0 ~3: All tests skipped.""");
     });
 
     test("runs skipped tests along with successful tests", () {
       _expectReport("""
           test('skip 1', () {}, skip: true);
           test('success 1', () {});
           test('skip 2', () {}, skip: true);
           test('success 2', () {});""",
           """
           +0: skip 1
@@ skipping 33 matching lines @@
       _expectReport("""
           test('skip 1', () {}, skip: 'some reason');
           test('skip 2', () {}, skip: 'or another');""",
           """
           +0: skip 1
             Skip: some reason
           +0 ~1: skip 2
             Skip: or another
           +0 ~2: All tests skipped.""");
     });
+
+    test("runs skipped tests with --run-skipped", () {
+      _expectReport("""
+          test('skip 1', () {}, skip: 'some reason');
+          test('skip 2', () {}, skip: 'or another');""",
+          """
+          +0: skip 1
+          +1: skip 2
+          +2: All tests passed!""",
+          args: ["--run-skipped"]);
+    });
   });
 }
 
-void _expectReport(String tests, String expected) {
+void _expectReport(String tests, String expected, {List<String> args}) {
   var dart = """
 import 'dart:async';
 
 import 'package:test/test.dart';
 
 void main() {
 $tests
 }
 """;
 
   d.file("test.dart", dart).create();
 
-  var test = runTest(["test.dart"]);
+  var test = runTest(["test.dart"]..addAll(args ?? []));
   test.shouldExit();
 
   schedule(() async {
     var stdoutLines = await test.stdoutStream().toList();
 
     // Remove excess trailing whitespace and trim off timestamps.
     var actual = stdoutLines.map((line) {
       if (line.startsWith("  ") || line.isEmpty) return line.trimRight();
       return line.trim().replaceFirst(new RegExp("^[0-9]{2}:[0-9]{2} "), "");
     }).join("\n");
 
     // Un-indent the expected string.
     var indentation = expected.indexOf(new RegExp("[^ ]"));
     expected = expected.split("\n").map((line) {
       if (line.isEmpty) return line;
       return line.substring(indentation);
     }).join("\n");
 
     expect(actual, equals(expected));
   });
 }