refactor(useRafTimeout): optimize useEffect cleanup fn (alibaba#2420)

Author: coding-ice

packages/hooks/src/useRafTimeout/index.ts

@@ -46,24 +46,20 @@ function useRafTimeout(fn: () => void, delay: number | undefined) {
   const fnRef = useLatest(fn);
   const timerRef = useRef<Handle>();
 
+  const clear = useCallback(() => {
+    if (timerRef.current) {
+      clearRafTimeout(timerRef.current);
+    }
+  }, []);
+
   useEffect(() => {
     if (!isNumber(delay) || delay < 0) return;
     timerRef.current = setRafTimeout(() => {
       fnRef.current();
     }, delay);
-    return () => {
-      if (timerRef.current) {
-        clearRafTimeout(timerRef.current);
-      }
-    };
+    return clear;
   }, [delay]);
 
-  const clear = useCallback(() => {
-    if (timerRef.current) {
-      clearRafTimeout(timerRef.current);
-    }
-  }, []);
-
   return clear;
 }