Fix component margin and padding values to use @line-height-computed

less/mixins.less

@@ -340,7 +340,7 @@
 // Dividers (basically an hr) within dropdowns and nav lists
 .nav-divider(@top: #e5e5e5, @bottom: #fff) {
   height: 2px; // 1px for background, one for border
-  margin: ((@line-height-base / 2) - 1) 0;
+  margin: ((@line-height-computed / 2) - 1) 0;
   overflow: hidden;
   background-color: @top;
   border-bottom: 1px solid @bottom;