Add an experimental permissions API for extensions.

chrome/browser/extensions/extension_permissions_api_constants.cc

Index: chrome/browser/extensions/extension_permissions_api_constants.cc
diff --git a/chrome/browser/extensions/extension_permissions_api_constants.cc b/chrome/browser/extensions/extension_permissions_api_constants.cc
new file mode 100644
index 0000000000000000000000000000000000000000..5d75ccda3b5e6115d1bcdb100e9ca9c54b92af5b
--- /dev/null
+++ b/chrome/browser/extensions/extension_permissions_api_constants.cc
@@ -0,0 +1,23 @@
+// 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_permissions_api_constants.h"
+
+namespace extension_permissions_module_constants {
+
+const char kApisKey[] = "permissions";
+
+const char kCantRemoveRequiredPermissionsError[] =
+    "You cannot remove required permissions.";
+const char kNotInOptionalPermissionsError[] =
+    "Optional permissions must be listed in extension manifest.";
+const char kNotWhitelistedError[] =
+    "The optional permissions API does not support '%s'.";
+const char kUnknownPermissionError[] =
+    "'%s' is not a recognized permission.";
+
+const char kOnAdded[] = "experimental.permissions.onAdded";
+const char kOnRemoved[] = "experimental.permissions.onRemoved";
+
+};  // namespace extension_permissions_module_constants