fix leaving the unfinished unmount warning

Author: jljsj33

src/QueueAnim.jsx

@@ -2,28 +2,28 @@ import React, { createElement, cloneElement } from 'react';
 import { findDOMNode } from 'react-dom';
 
 const _ease = {
-  easeInElastic: function(_p, o, t) {
+  easeInElastic: (_p, o, t) => {
     let p = _p;
     const _p1 = o >= 1 ? o : 1;
     const _p2 = (t || 1) / (o < 1 ? o : 1);
     const _p3 = _p2 / Math.PI * 2 * (Math.asin(1 / _p1) || 0);
     return -(_p1 * Math.pow(2, 10 * (p -= 1)) * Math.sin((p - _p3) * _p2));
   },
-  easeOutElastic: function(p, o, t) {
+  easeOutElastic: (p, o, t) => {
     const _p1 = o >= 1 ? o : 1;
     const _p2 = (t || 1) / (o < 1 ? o : 1);
     const _p3 = _p2 / Math.PI * 2 * (Math.asin(1 / _p1) || 0);
     return _p1 * Math.pow(2, -10 * p) * Math.sin((p - _p3) * _p2) + 1;
   },
-  easeInOutElastic: function(_p, o, t) {
+  easeInOutElastic: (_p, o, t) => {
     let p = _p;
     const _p1 = o >= 1 ? o : 1;
     const _p2 = (t || 1) / (o < 1 ? o : 1);
     const _p3 = _p2 / Math.PI * 2 * (Math.asin(1 / _p1) || 0);
     p *= 2;
     return p < 1 ? -0.5 * (_p1 * Math.pow(2, 10 * (p -= 1)) * Math.sin((p - _p3) * _p2)) : _p1 * Math.pow(2, -10 * (p -= 1)) * Math.sin((p - _p3) * _p2) * 0.5 + 1;
   },
-  easeInBounce: function(_p) {
+  easeInBounce: (_p) => {
     let p = _p;
     const __p = 1 - p;
     if (__p < 1 / 2.75) {
@@ -35,7 +35,7 @@ const _ease = {
     }
     return 1 - (7.5625 * (p -= 2.625 / 2.75) * p + 0.984375);
   },
-  easeOutBounce: function(_p) {
+  easeOutBounce: (_p) => {
     let p = _p;
     if (p < 1 / 2.75) {
       return 7.5625 * p * p;
@@ -46,7 +46,7 @@ const _ease = {
     }
     return 7.5625 * (p -= 2.625 / 2.75) * p + 0.984375;
   },
-  easeInOutBounce: function(_p) {
+  easeInOutBounce: (_p) => {
     let p = _p;
     const invert = (p < 0.5);
     if (invert) {
@@ -82,9 +82,9 @@ if (typeof document !== 'undefined' && typeof window !== 'undefined') {
     const callback = arguments[arguments.length - 1];
     // call after stack flushes
     // in case you app depends on the asyncron nature of this function
-    setImmediate(function() {
-      callback();
-    });
+    setImmediate(() =>
+      callback()
+    );
   };
 }
 
@@ -193,16 +193,12 @@ class QueueAnim extends React.Component {
   }
 
   componentWillUnmount() {
-    if (this.originalChildren && this.originalChildren.length > 0) {
-      this.originalChildren.forEach(child => {
-        if (child && this.refs[child.key]) {
-          velocity(findDOMNode(this.refs[child.key]), 'stop');
-        }
-      });
-      Object.keys(this.placeholderTimeoutIds).forEach(key => {
-        clearTimeout(this.placeholderTimeoutIds[key]);
-      });
-    }
+    [].concat(this.keysToEnter, this.keysToLeave, this.keysAnimating).forEach(key =>
+      velocity(findDOMNode(this.refs[key]), 'stop')
+    );
+    Object.keys(this.placeholderTimeoutIds).forEach(key => {
+      clearTimeout(this.placeholderTimeoutIds[key]);
+    });
   }
 
   getVelocityConfig(index, ...args) {