[actionbar] Add gap b/w action-icon buttons and their drop down menus

File-ng requires an 8px vertical gap between any action-icon and their
drop down menu. Action icon have a 48px x 48px tap target and the drop
down menu should not overlap that tap target, hence the 8px gap.

Bug: 1066727
Change-Id: Ic91d2fda156abb359e5110c32488b9b1cec41406
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2298847Reviewed-by: Alex Danilo <adanilo@chromium.org>
Commit-Queue: Noel Gordon <noel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#788517}

ui/file_manager/file_manager/foreground/css/file_manager.css

@@ -3382,6 +3382,13 @@ list.autocomplete-suggestions > [lead] {
   margin-top: 2px;
 }
 
+body.files-ng #gear-menu,
+body.files-ng #share-menu,
+body.files-ng #sort-menu,
+body.files-ng #tasks-menu {
+  margin-top: 8px;
+}
+
 #gear-menu > cr-menu-item:not(.menuitem-button),
 #sort-menu > cr-menu-item {
   margin-inline-end: 50px;