Vertically align group container on the middle

So the label in the group and outside the group on the same row are aligned.

issue9845
review329641002

src/sao.less

@@ -651,6 +651,9 @@ img.icon {
             font-size: @font-size-base;
             margin-bottom: 5px;
         }
+        .form-container, .form-hcontainer, .form-vcontainer {
+            vertical-align: middle;
+        }
     }
 }