Update charted to 0.4.8 and roll

packages/collection/test/combined_wrapper/iterable_test.dart

+// Copyright (c) 2017, 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:collection/collection.dart';
+import 'package:test/test.dart';
+
+void main() {
+  var iterable1 = new Iterable.generate(3);
+  var iterable2 = new Iterable.generate(3, (i) => i + 3);
+  var iterable3 = new Iterable.generate(3, (i) => i + 6);
+
+  test('should combine multiple iterables when iterating', () {
+    var combined = new CombinedIterableView([iterable1, iterable2, iterable3]);
+    expect(combined, [0, 1, 2, 3, 4, 5, 6, 7, 8]);
+  });
+
+  test('should combine multiple iterables with some empty ones', () {
+    var combined =
+        new CombinedIterableView([iterable1, [], iterable2, [], iterable3, []]);
+    expect(combined, [0, 1, 2, 3, 4, 5, 6, 7, 8]);
+  });
+
+  test('should function as an empty iterable when no iterables are passed', () {
+    var empty = new CombinedIterableView([]);
+    expect(empty, isEmpty);
+  });
+
+  test('should function as an empty iterable with all empty iterables', () {
+    var empty = new CombinedIterableView([[], [], []]);
+    expect(empty, isEmpty);
+  });
+
+  test('should reflect changes from the underlying iterables', () {
+    var list1 = [];
+    var list2 = [];
+    var combined = new CombinedIterableView([list1, list2]);
+    expect(combined, isEmpty);
+    list1.addAll([1, 2]);
+    list2.addAll([3, 4]);
+    expect(combined, [1, 2, 3, 4]);
+    expect(combined.last, 4);
+    expect(combined.first, 1);
+  });
+
+  test('should reflect changes from the iterable of iterables', () {
+    var iterables = <Iterable>[];
+    var combined = new CombinedIterableView(iterables);
+    expect(combined, isEmpty);
+    expect(combined, hasLength(0));
+
+    iterables.add(iterable1);
+    expect(combined, isNotEmpty);
+    expect(combined, hasLength(3));
+
+    iterables.clear();
+    expect(combined, isEmpty);
+    expect(combined, hasLength(0));
+  });
+}