Fix type checking of void type.

tests/language/void_type_test.dart

Index: tests/language/void_type_test.dart
===================================================================
--- tests/language/void_type_test.dart	(revision 0)
+++ tests/language/void_type_test.dart	(revision 0)
@@ -0,0 +1,84 @@
+// Copyright (c) 2012, 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.
+// Dart test for type checks involving the void type.
+
+isCheckedMode() {
+  try {
+    var i = 1;
+    String s = i;
+    return false;
+  } catch(var e) {
+    return true;
+  }
+}
+
+void f() { return; }
+
+void f_null() { return null; }
+
+void f_1() { return 1; }
+
+void f_dyn_null() {
+  var x = null;
+  return x;
+}
+
+void f_dyn_1() {
+  var x = 1;
+  return x;
+}
+
+void f_f() { return f(); }
+
+void test(int n, void func(), bool must_get_error) {
+  // Test as closure call.
+  {
+    bool got_type_error = false;
+    try {
+      var x = func();
+    } catch (TypeError error) {
+      got_type_error = true;
+    }
+    // Never a type error in production mode.
+    if (isCheckedMode()) {
+      Expect.isTrue(got_type_error == must_get_error);
+    } else {
+      Expect.isFalse(got_type_error);
+    }
+  }
+  // Test as direct call.
+  {
+    bool got_type_error = false;
+    try {
+      var x;
+      switch (n) {
+        case 0: x = f(); break;
+        case 1: x = f_null(); break;
+        case 2: x = f_1(); break;
+        case 3: x = f_dyn_null(); break;
+        case 4: x = f_dyn_1(); break;
+        case 5: x = f_f(); break;
+      }
+    } catch (TypeError error) {
+      got_type_error = true;
+    }
+    // Never a type error in production mode.
+    if (isCheckedMode()) {
+      Expect.isTrue(got_type_error == must_get_error);
+    } else {
+      Expect.isFalse(got_type_error);
+    }
+  }
+}
+
+main() {
+  test(0, f, false);
+  test(1, f_null, false);
+  test(2, f_1, true);
+  test(3, f_dyn_null, false);
+  test(4, f_dyn_1, true);
+  test(5, f_f, false);
+}
+
+