add size-xxx-small utility class

Dottenpixel · Dottenpixel · commit 69d0eb2791c1 · 2017-09-28T08:57:51.000-07:00
diff --git a/ui/utilities/sizing/_index.scss b/ui/utilities/sizing/_index.scss
@@ -5,6 +5,7 @@
 /// @type map
 /// @private
 $_sizes: (
+  'xxx-small,': $size-xxx-small,
   'xx-small': $size-xx-small,
   'x-small': $size-x-small,
   'small': $size-small,
