:white_check_mark: Fix react-dnd demo broken in react 15
:white_check_mark: Fix react-dnd demo broken in react 15

elevensky/ant-design,elevensky/ant-design,elevensky/ant-design,icaife/ant-design,zheeeng/ant-design,zheeeng/ant-design,ant-design/ant-design,ant-design/ant-design,icaife/ant-design,icaife/ant-design,zheeeng/ant-design,ant-design/ant-design,icaife/ant-design,elevensky/ant-design,ant-design/ant-design,zheeeng/ant-design