[DevTools] permanently polyfill for rAF in devtools_page (#26193)

## Summary

We had this as a temporary fix for #24626. Now that Chrome team decides
to turn the flag on again (with good reasons explained in
https://bugs.chromium.org/p/chromium/issues/detail?id=1241986#c31), we
will turn it into a long term solution.
In the future, we want to explore whether we can render React elements
on panel.html instead, as `requestAnimationFrame` produces higher
quality animation.

## How did you test this change?

Tested on local build with "Throttle non-visible cross-origin iframes"
flag enabled.

packages/react-devtools-extensions/src/main.js

@@ -30,29 +30,20 @@ const LOCAL_STORAGE_SUPPORTS_PROFILING_KEY =
 const isChrome = getBrowserName() === 'Chrome';
 const isEdge = getBrowserName() === 'Edge';
 
-// since Chromium v102, requestAnimationFrame no longer fires in devtools_page (i.e. this file)
-// mock requestAnimationFrame with setTimeout as a temporary workaround
-// https://github.com/facebook/react/issues/24626
-if (isChrome || isEdge) {
-  const timeoutID = setTimeout(() => {
-    // if requestAnimationFrame is not working, polyfill it
-    // The polyfill is based on https://gist.github.com/jalbam/5fe05443270fa6d8136238ec72accbc0
-    const FRAME_TIME = 16;
-    let lastTime = 0;
-    window.requestAnimationFrame = function (callback, element) {
-      const now = window.performance.now();
-      const nextTime = Math.max(lastTime + FRAME_TIME, now);
-      return setTimeout(function () {
-        callback((lastTime = nextTime));
-      }, nextTime - now);
-    };
-    window.cancelAnimationFrame = clearTimeout;
-  }, 400);
-
-  requestAnimationFrame(() => {
-    clearTimeout(timeoutID);
-  });
-}
+// rAF never fires on devtools_page (because it's in the background)
+// https://bugs.chromium.org/p/chromium/issues/detail?id=1241986#c31
+// Since we render React elements here, we need to polyfill it with setTimeout
+// The polyfill is based on https://gist.github.com/jalbam/5fe05443270fa6d8136238ec72accbc0
+const FRAME_TIME = 16;
+let lastTime = 0;
+window.requestAnimationFrame = function (callback, element) {
+  const now = window.performance.now();
+  const nextTime = Math.max(lastTime + FRAME_TIME, now);
+  return setTimeout(function () {
+    callback((lastTime = nextTime));
+  }, nextTime - now);
+};
+window.cancelAnimationFrame = clearTimeout;
 
 let panelCreated = false;