deps: replace rcUtil.classSet with classNames

package.json

@@ -50,6 +50,7 @@
     "lint"
   ],
   "dependencies": {
+    "classnames": "^2.2.1",
     "rc-tooltip": "3.x",
     "rc-util": "3.x"
   }

src/Dots.jsx

@@ -1,5 +1,5 @@
 import React from 'react';
-import { classSet } from 'rc-util';
+import classNames from 'classnames';
 
 function calcPoints(marks, dots, step, min, max) {
   const points = Object.keys(marks).map(parseFloat);
@@ -19,7 +19,7 @@ const Dots = ({prefixCls, marks, dots, step, included, lowerBound, upperBound, m
 
     const isActived = (!included && point === upperBound) ||
             (included && point <= upperBound && point >= lowerBound);
-    const pointClassName = classSet({
+    const pointClassName = classNames({
       [prefixCls + '-dot']: true,
       [prefixCls + '-dot-active']: isActived,
     });

src/Marks.jsx

@@ -1,5 +1,5 @@
 import React from 'react';
-import rcUtil from 'rc-util';
+import classNames from 'classnames';
 
 const Marks = ({className, marks, included, upperBound, lowerBound, max, min}) => {
   const marksKeys = Object.keys(marks);
@@ -11,7 +11,7 @@ const Marks = ({className, marks, included, upperBound, lowerBound, max, min}) =
   const elements = marksKeys.map(parseFloat).map((point) => {
     const isActived = (!included && point === upperBound) ||
             (included && point <= upperBound && point >= lowerBound);
-    const markClassName = rcUtil.classSet({
+    const markClassName = classNames({
       [className + '-text']: true,
       [className + '-text-active']: isActived,
     });

src/Slider.jsx

@@ -1,5 +1,6 @@
 import React from 'react';
-import {Dom as DomUtils, classSet} from 'rc-util';
+import {Dom as DomUtils} from 'rc-util';
+import classNames from 'classnames';
 import Track from './Track';
 import Handle from './Handle';
 import Dots from './Dots';
@@ -311,7 +312,7 @@ class Slider extends React.Component {
                        offset={lowerOffset} value={lowerBound} dragging={handle === 'lowerBound'} />);
     }
 
-    const sliderClassName = classSet({
+    const sliderClassName = classNames({
       [prefixCls]: true,
       [prefixCls + '-disabled']: disabled,
       [className]: !!className,