[sensors] Add Permission guard to the generic sensor apis.

third_party/WebKit/public/platform/modules/permissions/WebPermissionType.h

 // Copyright 2015 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 WebPermissionType_h
 #define WebPermissionType_h
 
 namespace blink {
 
 enum WebPermissionType {
   WebPermissionTypeGeolocation,
   WebPermissionTypeNotifications,
   WebPermissionTypePush,
   WebPermissionTypePushNotifications,
   WebPermissionTypeMidi,
   WebPermissionTypeMidiSysEx,
   WebPermissionTypeDurableStorage,
   WebPermissionTypeBackgroundSync,
+  WebPermissionTypeSensors,
 
   WebPermissionTypeLast,
 };
 
 }  // namespace blink
 
 #endif  // WebPermissionType_h