Implement requestIdleCallback API

Source/core/dom/IdleCallbackDeadline.idl

Index: Source/core/dom/IdleCallbackDeadline.idl
diff --git a/Source/modules/nfc/NFC.idl b/Source/core/dom/IdleCallbackDeadline.idl
similarity index 52%
copy from Source/modules/nfc/NFC.idl
copy to Source/core/dom/IdleCallbackDeadline.idl
index 6deb627fa84205671648c544f8726599b00fd583..57fb6687a936c33110af01f3dec4307a995a7b15 100644
--- a/Source/modules/nfc/NFC.idl
+++ b/Source/core/dom/IdleCallbackDeadline.idl
@@ -2,12 +2,10 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// https://w3c.github.io/web-nfc/#idl-def-NFC
-
 [
   GarbageCollected,
-  ActiveDOMObject,
-  RuntimeEnabled=WebNFC,
-] interface NFC {
-   [CallWith=ScriptState] Promise<NFCAdapter> requestAdapter ();
+  RuntimeEnabled=RequestIdleCallback,
+] interface IdleCallbackDeadline {
+    readonly attribute double timeRemaining;
+    readonly attribute boolean didTimeout;
 };