Support general expressions as keys in literal maps.

tests/language/map_literal5_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.
+
+// Test the use of general expression as keys in map literals.
+
+library map_literal5_test;
+
+import "package:expect/expect.dart";
+
+void main() {
+  test(true);
+  test(false);
+}
+
+void test(bool b) {
+  var m = create(b);
+  Expect.equals(b, m.containsKey(true));
+  Expect.equals(b, m.containsKey(2));
+  Expect.equals(b, m.containsKey(1));
+  Expect.equals(!b, m.containsKey(false));
+  Expect.equals(!b, m.containsKey("bar"));
+  Expect.equals(!b, m.containsKey("foo"));
+  if (b) {
+    Expect.equals(0, m[true]);
+    Expect.equals(3, m[2]);
+    Expect.equals(2, m[1]);
+  } else {
+    Expect.equals(0, m[false]);
+    Expect.equals("baz", m["bar"]);
+    Expect.equals(2, m["foo"]);
+  }
+}
+
+create(bool b) {
+  return {
+    b: 0,
+    m(b): n(b),
+    b ? 1 : "foo": 2,
+  };
+}
+
+m(bool b) => b ? 2 : "bar";
+n(bool b) => b ? 3 : "baz";