Add IDL and stub implementation for chrome.usersPrivate API.

extensions/common/permissions/api_permission.h

 // Copyright 2013 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.
 
 #ifndef EXTENSIONS_COMMON_PERMISSIONS_API_PERMISSION_H_
 #define EXTENSIONS_COMMON_PERMISSIONS_API_PERMISSION_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 222 matching lines @@
     kMediaGalleriesAllGalleriesRead,
     kNetworkState,
     kOverrideBookmarksUI,
     kShouldWarnAllHosts,
     kSocketAnyHost,
     kSocketDomainHosts,
     kSocketSpecificHosts,
     kUsbDeviceList,
     kUsbDeviceUnknownProduct,
     kUsbDeviceUnknownVendor,
+    kUsersPrivate,
     // Last entry: Add new entries above and ensure to update the
     // "ExtensionPermission3" enum in tools/metrics/histograms/histograms.xml
     // (by running update_extension_permission.py).
     kEnumBoundary
   };
 
   struct CheckParam {
   };
 
   explicit APIPermission(const APIPermissionInfo* info);
@@ skipping 199 matching lines @@
   const char* const name_;
   const int flags_;
   const int l10n_message_id_;
   const PermissionMessage::ID message_id_;
   const APIPermissionConstructor api_permission_constructor_;
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_COMMON_PERMISSIONS_API_PERMISSION_H_