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

third_party/WebKit/public/platform/modules/permissions/permission.mojom

 // 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.
 
 module blink.mojom;
 
 import "third_party/WebKit/public/platform/modules/permissions/permission_status.mojom";
 import "url/mojo/origin.mojom";
 
 enum PermissionName {
   GEOLOCATION,
   NOTIFICATIONS,
   PUSH_NOTIFICATIONS,
   MIDI,
   PROTECTED_MEDIA_IDENTIFIER,
   DURABLE_STORAGE,
   AUDIO_CAPTURE,
   VIDEO_CAPTURE,
   BACKGROUND_SYNC,
+  SENSORS,
 };
 
 struct MidiPermissionDescriptor {
   bool sysex;
 };
 
 // Union of possible extensions to the base PermissionDescriptor type.
 union PermissionDescriptorExtension {
   MidiPermissionDescriptor midi;
 };
@@ skipping 22 matching lines @@
 
   // Runs the callback next time there is a permission status change for the
   // given { permission, origin }. Callers of this method will have to call it
   // again if they want to keep listening to the changes. To prevent race
   // conditions, the caller must pass the last known value.
   GetNextPermissionChange(PermissionDescriptor permission,
                           url.mojom.Origin origin,
                           PermissionStatus last_known_status)
     => (PermissionStatus status);
 };