Added a private chromeAuthPrivate API.

chrome/test/data/extensions/api_test/chrome_auth_private/installed_component_app/cloud_print_fail.js

Index: chrome/test/data/extensions/api_test/chrome_auth_private/installed_component_app/cloud_print_fail.js
diff --git a/chrome/test/data/extensions/api_test/chrome_auth_private/installed_component_app/cloud_print_fail.js b/chrome/test/data/extensions/api_test/chrome_auth_private/installed_component_app/cloud_print_fail.js
new file mode 100644
index 0000000000000000000000000000000000000000..c5db1102b6e1eb3eaa7280d2ecae7572d00bef38
--- /dev/null
+++ b/chrome/test/data/extensions/api_test/chrome_auth_private/installed_component_app/cloud_print_fail.js
@@ -0,0 +1,19 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// This test is invoked from an installed component app. Since we have an
+// explicit URL check in the API, this should fail.
+var tests = [
+  function failureSetCreds() {
+    var expectedError = "Cannot call this API from a non-cloudprint URL."
+    var userEmail = 'foo@gmail.com';
+    var robotEmail = 'foorobot@googleusercontent.com';
+    var credentials = '1/23546efa54';
+    chrome.chromeAuthPrivate.setCloudPrintCredentials(
+        userEmail, robotEmail, credentials,
+        chrome.test.callbackFail(expectedError));
+  }
+];
+
+chrome.test.runTests(tests);