Big merge from experimental to bleeding edge.

tests/language/double_to_string_as_precision3_test.dart

+// 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.
+// Test basic integer operations.
+
+main() {
+  Expect.equals("0.000555000000000000046248",
+                (0.000555).toStringAsPrecision(21));
+  Expect.equals(0.000555000000000000046248, 0.000555);
+  Expect.equals("5.54999999999999980179e-7",
+                (0.000000555).toStringAsPrecision(21));
+  Expect.equals(5.54999999999999980179e-7, 0.000000555);
+  Expect.equals("-5.54999999999999980179e-7",
+                (-0.000000555).toStringAsPrecision(21));
+  Expect.equals(-5.54999999999999980179e-7, -0.000000555);
+}