Fix notFoundContent not working in AutoComplete, close #8553

components/select/demo/search-box.md

@@ -70,7 +70,6 @@ class SearchInput extends React.Component {
         mode="combobox"
         value={this.state.value}
         placeholder={this.props.placeholder}
-        notFoundContent=""
         style={this.props.style}
         defaultActiveFirstOption={false}
         showArrow={false}

components/select/index.tsx

@@ -134,8 +134,9 @@ export default class Select extends React.Component<SelectProps, {}> {
       combobox: isCombobox,
     };
 
+    // AutoComplete don't have notFoundContent defaultly
     const notFoundContentLocale = isCombobox ?
-      null : notFoundContent || locale.notFoundContent;
+      (notFoundContent || '') : (notFoundContent || locale.notFoundContent);
     return (
       <RcSelect
         {...restProps}