Merge pull request #330 from ant-design/fix/328

progress bar style bugfix

style/components/progress.less

@@ -28,6 +28,7 @@
     border-radius: 100px;
     background-color: @primary-color;
     transition: all 0.3s linear 0s;
+    position: relative;
   }
   &-line-text {
     position: absolute;