[dashboard] adding an option to duplicate slices when "Saving AS" (#3391)

* [dashboard] adding an option to duplicate slices when "Saving AS"

* Fix tests

superset/assets/javascripts/explore/components/controls/CheckboxControl.jsx

@@ -1,6 +1,7 @@
 import React from 'react';
 import PropTypes from 'prop-types';
 import ControlHeader from '../ControlHeader';
+import Checkbox from '../../../components/Checkbox';
 
 const propTypes = {
   name: PropTypes.string.isRequired,
@@ -15,24 +16,22 @@ const defaultProps = {
   onChange: () => {},
 };
 
+const checkboxStyle = { paddingRight: '5px' };
+
 export default class CheckboxControl extends React.Component {
-  onToggle() {
-    this.props.onChange(!this.props.value);
+  onChange(checked) {
+    this.props.onChange(checked);
   }
   render() {
     return (
       <ControlHeader
         {...this.props}
-        onClick={this.onToggle.bind(this)}
         leftNode={
-          <span>
-            <i
-              className={`fa fa-check ${this.props.value ? 'text-primary' : 'text-transparent'}`}
-              onClick={this.onToggle.bind(this)}
-              style={{ border: '1px solid #aaa', borderRadius: '2px', cursor: 'pointer' }}
-            />
-            &nbsp;&nbsp;
-          </span>
+          <Checkbox
+            onChange={this.onChange.bind(this)}
+            style={checkboxStyle}
+            checked={!!this.props.value}
+          />
         }
       />
     );