use number for requestIdleCallback handle

Author: Critteros

packages/react-native/__typetests__/globals.tsx

@@ -138,6 +138,9 @@ function testRequestAnimationFrame(){
 }
 
 function testRequestIdleCallback() {
+    cancelIdleCallback(null);
+    cancelIdleCallback(undefined);
+
     let handle = requestIdleCallback(deadline => {
         const didTimeout: boolean = deadline.didTimeout;
         const remaining: number = deadline.timeRemaining();
@@ -151,9 +154,8 @@ function testRequestIdleCallback() {
     // @ts-expect-error
     requestIdleCallback(noop, { timeout: 'wrong-type' });
 
-    // handle is opaque: object on New Architecture, number on legacy
     // @ts-expect-error
-    const handleIsNotNumber: number = requestIdleCallback(noop);
+    cancelIdleCallback('wrong-type');
 }
 
 const fetchCopy: WindowOrWorkerGlobalScope['fetch'] = fetch;

packages/react-native/src/types/globals.d.ts

@@ -125,15 +125,14 @@ declare global {
   function cancelAnimationFrame(handle: number | null | undefined): void;
   function requestAnimationFrame(callback: (time: number) => void): number;
 
-  type IdleCallbackID = unknown;
   function requestIdleCallback(
     callback: (deadline: {
       didTimeout: boolean;
       timeRemaining: () => number;
     }) => void,
     options?: {timeout: number},
-  ): IdleCallbackID;
-  function cancelIdleCallback(handle: IdleCallbackID): void;
+  ): number;
+  function cancelIdleCallback(handle: number | null | undefined): void;
 
   function fetchBundle(
     bundleId: number,