Fix issue 13474. Simplify graph builder for Boolean operators AND, OR: do not optimize code when th…

tests/language/issue13474_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.
+// VMOptions=--enable_type_checks
+
+import "package:expect/expect.dart";
+
+main() {
+  var a;
+  Expect.throws(() { true && (a = 5); }, (error) => error is TypeError);
+  Expect.throws(() { (a = 5) && true; }, (error) => error is TypeError);
+  Expect.throws(() { false || (a = 5); }, (error) => error is TypeError);
+  Expect.throws(() { (a = 5) || false; }, (error) => error is TypeError);
+  Expect.throws(() { (a = 5) || true; }, (error) => error is TypeError);
+
+  // No exceptions thrown.
+  false && (a = 5);
+  true || (a = 5);
+}
+