Moving slow parts to <RenderDelay/>

Signed-off-by: Alex Andreev <alex.andreev.email@gmail.com>

types/dom.d.ts

@@ -24,4 +24,9 @@ declare global {
   interface Element {
     scrollIntoViewIfNeeded(opt_center?: boolean): void;
   }
+
+  interface Window {
+    requestIdleCallback(callback: () => void);
+    cancelIdleCallback(callback: () => void);
+  }
 }