Check for return types on setters (#122).

test/rules/avoid_return_types_on_setters.dart

Index: test/rules/avoid_return_types_on_setters.dart
diff --git a/test/rules/avoid_return_types_on_setters.dart b/test/rules/avoid_return_types_on_setters.dart
new file mode 100644
index 0000000000000000000000000000000000000000..d72aa472fba666447a195990b7e7d407c397397d
--- /dev/null
+++ b/test/rules/avoid_return_types_on_setters.dart
@@ -0,0 +1,16 @@
+// Copyright (c) 2016, 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.
+
+// test w/ `dart test/util/solo_test.dart avoid_return_types_on_setters`
+
+set speed(int ms) {} //OK
+void set speed2(int ms) {} //LINT
+
+class Car {
+  static set make(String name) {} // OK
+  static void set model(String name) {} //LINT
+
+  set speed(int ms) {} //OK
+  void set speed2(int ms) {} //LINT
+}