Fix in test_runner_test, moved dependency_graph_test to standalone/io

tests/utils/dependency_graph_test.dart

-// 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 '../../tools/testing/dart/dependency_graph.dart' as graph;
-
-main() {
-  var dgraph = new graph.Graph();
-  var numberOfEvents = 0;
-  var eventAssertions = [];
-
-  graph.Node newNode(int i, List deps) {
-    graph.Node node = dgraph.newNode(i, deps);
-    Expect.isTrue(node.userData == i);
-    Expect.isTrue(dgraph.nodes.contains(node));
-    for (var dep in deps) {
-      Expect.isTrue(node.dependencies.contains(dep));
-      Expect.isTrue(dep.neededFor.contains(node));
-    }
-
-    numberOfEvents++;
-    eventAssertions.add((event) {
-      Expect.isTrue(event is graph.NodeAddedEvent);
-      Expect.isTrue(event.node == node);
-    });
-
-    return node;
-  }
-
-  changeState(graph.Node node, graph.NodeState newState) {
-    var oldState = node.state;
-
-    dgraph.changeState(node, newState);
-    Expect.isTrue(node.state == newState);
-
-    numberOfEvents++;
-    eventAssertions.add((event) {
-      Expect.isTrue(event is graph.StateChangedEvent);
-      Expect.isTrue(event.node == node);
-      Expect.isTrue(event.from == oldState);
-      Expect.isTrue(event.to == newState);
-    });
-  }
-
-  var node1, node2, node3;
-
-  node1 = newNode(1, []);
-  changeState(node1, graph.NodeState.Processing);
-  node2 = newNode(2, [node1]);
-  changeState(node1, graph.NodeState.Successful);
-  node3 = newNode(3, [node1, node2]);
-  changeState(node2, graph.NodeState.Failed);
-  changeState(node3, graph.NodeState.UnableToRun);
-
-  dgraph.events.take(numberOfEvents).toList().then((events) {
-    for (var i=0; i<events.length; i++) {
-      eventAssertions[i](events[i]);
-    }
-  });
-}