Merge pull request #2468 from edx/marco/studio/fix/component-header-styling

Added back in component header visual separation from component renderin...

cms/static/sass/views/_unit.scss

@@ -877,10 +877,12 @@ body.unit {
     .wrapper-component-action-header {
       @include box-sizing(border-box);
       position: absolute;
-      width: 100%;
-      padding: $baseline/4 $baseline/2;
       top: 0;
       left: 0;
+      padding: $baseline/4 $baseline/2;
+      width: 100%;
+      border-bottom: 1px solid $gray-l4;
+      background-color: $gray-l6;
     }
 
     .component-header {
@@ -890,7 +892,7 @@ body.unit {
       max-width: 60%;
       color: $gray-l1;
       text-overflow: ellipsis;
-      white-space: nowrap; 
+      white-space: nowrap;
       font-weight: 300;
     }