add all frontend files

node_modules/rc-virtual-list/lib/utils/scrollbarUtil.js

@@ -0,0 +1,17 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.getSpinSize = getSpinSize;
+var MIN_SIZE = 20;
+function getSpinSize() {
+  var containerSize = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : 0;
+  var scrollRange = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : 0;
+  var baseSize = containerSize / scrollRange * containerSize;
+  if (isNaN(baseSize)) {
+    baseSize = 0;
+  }
+  baseSize = Math.max(baseSize, MIN_SIZE);
+  return Math.floor(baseSize);
+}