BatteryStatus: use 'unrestricted double' instead of 'double'

Source/modules/battery/BatteryManager.idl

Index: Source/modules/battery/BatteryManager.idl
diff --git a/Source/modules/battery/BatteryManager.idl b/Source/modules/battery/BatteryManager.idl
index 2a28c73c2492dbdfe7ffedb8dc559cb63e61da75..01a6ce1d7efe468d6c394e97d552600270c9c01c 100644
--- a/Source/modules/battery/BatteryManager.idl
+++ b/Source/modules/battery/BatteryManager.idl
@@ -2,13 +2,14 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// http://dev.w3.org/2009/dap/system-info/battery-status.html
+// https://dvcs.w3.org/hg/dap/raw-file/tip/battery/Overview.html#batterymanager-interface
 [
     RuntimeEnabled=BatteryStatus,
+    TypeChecking=Unrestricted,
 ] interface BatteryManager : EventTarget {
     readonly attribute boolean charging;
-    readonly attribute double chargingTime;
-    readonly attribute double dischargingTime;
+    readonly attribute unrestricted double chargingTime;
+    readonly attribute unrestricted double dischargingTime;
     readonly attribute double level;
 
     attribute EventHandler onchargingchange;
@@ -16,4 +17,3 @@
     attribute EventHandler ondischargingtimechange;
     attribute EventHandler onlevelchange;
 };
-