Fix XCObject._EncodeString() for unicode characters.

test/mac/gyptest-unicode-settings.py

Index: test/mac/gyptest-unicode-settings.py
diff --git a/test/mac/gyptest-unicode-settings.py b/test/mac/gyptest-unicode-settings.py
new file mode 100644
index 0000000000000000000000000000000000000000..db59f5619a312bca9fa273fafe8d4c1efbacb036
--- /dev/null
+++ b/test/mac/gyptest-unicode-settings.py
@@ -0,0 +1,20 @@
+#!/usr/bin/env python
+
+# Copyright (c) 2013 Google Inc. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""
+Verifies that unicode strings in 'xcode_settings' work.
+Also checks that ASCII control characters are escaped properly.
+"""
+
+import TestGyp
+
+import sys
+
+if sys.platform == 'darwin':
+  test = TestGyp.TestGyp(formats=['xcode'])
+  test.run_gyp('test.gyp', chdir='unicode-settings')
+  test.build('test.gyp', test.ALL, chdir='unicode-settings')
+  test.pass_test()