Add support for app_shell-only extension APIs

extensions/shell/browser/api/shell_identity/shell_identity_api_unittest.cc

+// Copyright 2014 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 "extensions/shell/browser/api/shell_identity/shell_identity_api.h"
+
+#include "base/memory/scoped_ptr.h"
+#include "base/values.h"
+#include "extensions/browser/api_unittest.h"
+
+namespace extensions {
+
+typedef ApiUnitTest ShellIdentityApiTest;
+
+// Verifies that the getAuthToken function exists and can be called without
+// crashing.
+TEST_F(ShellIdentityApiTest, GetAuthTokenBasics) {
+  scoped_ptr<base::Value> result =
+      RunFunctionAndReturnValue(new ShellIdentityGetAuthTokenFunction, "[]");
+
+  // Function returns nothing.
+  EXPECT_FALSE(result.get());
+}
+
+}  // namespace extensions