Implement chrome.systemPrivate.getIncognitoModeAvailability extension API function

chrome/browser/extensions/extension_system_apitest.cc

Index: chrome/browser/extensions/extension_system_apitest.cc
diff --git a/chrome/browser/extensions/extension_system_apitest.cc b/chrome/browser/extensions/extension_system_apitest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..3278b78ad3304fe248ac4c54ed0804f01382b646
--- /dev/null
+++ b/chrome/browser/extensions/extension_system_apitest.cc
@@ -0,0 +1,18 @@
+// 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.
+
+#include "chrome/browser/extensions/extension_apitest.h"
+#include "chrome/browser/prefs/pref_service.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/ui/browser.h"
+#include "chrome/common/pref_names.h"
+
+IN_PROC_BROWSER_TEST_F(ExtensionApiTest, SystemApi) {
+  PrefService* pref_service = browser()->profile()->GetPrefs();
+  pref_service->SetInteger(prefs::kIncognitoModeAvailability, 1);
+
+  EXPECT_TRUE(RunComponentExtensionTest("system")) << message_;
+
+  EXPECT_EQ(1, pref_service->GetInteger(prefs::kIncognitoModeAvailability));
+}