update doc

close #11802

components/table/index.en-US.md

@@ -61,6 +61,7 @@ const columns = [{
 | defaultExpandedRowKeys | Initial expanded row keys | string\[] | - |
 | expandedRowKeys | Current expanded row keys | string\[] | - |
 | expandedRowRender | Expanded container render for each row | Function(record, index, indent, expanded):ReactNode | - |
+| expandIcon | Customize row expand Icon. Ref [example](http://react-component.github.io/table/examples/expandIcon.html) | Function(props):ReactNode | - |
 | expandRowByClick | Whether to expand row by clicking anywhere in the whole row | boolean | `false` |
 | footer | Table footer renderer | Function(currentPageData) |  |
 | indentSize | Indent size in pixels of tree data | number | 15 |

components/table/index.zh-CN.md

@@ -66,6 +66,7 @@ const columns = [{
 | defaultExpandedRowKeys | 默认展开的行 | string\[] | - |
 | expandedRowKeys | 展开的行，控制属性 | string\[] | - |
 | expandedRowRender | 额外的展开行 | Function(record, index, indent, expanded):ReactNode | - |
+| expandIcon | 自定义展开图标，参考[示例](http://react-component.github.io/table/examples/expandIcon.html) | Function(props):ReactNode | - |
 | expandRowByClick | 通过点击行来展开子行 | boolean | `false` |
 | footer | 表格尾部 | Function(currentPageData) |  |
 | indentSize | 展示树形数据时，每层缩进的宽度，以 px 为单位 | number | 15 |