Fix clicking area below the scrollbar thumbs in Files app.

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

Index: ui/file_manager/file_manager/foreground/css/file_manager.css
diff --git a/ui/file_manager/file_manager/foreground/css/file_manager.css b/ui/file_manager/file_manager/foreground/css/file_manager.css
index dcf67a5c9d59eb5ba8c1901649e07141be897722..cb7c3019f697d1ca72f9b7e28c947a8e495ee1c7 100644
--- a/ui/file_manager/file_manager/foreground/css/file_manager.css
+++ b/ui/file_manager/file_manager/foreground/css/file_manager.css
@@ -65,6 +65,7 @@ a:focus {
 .scrollbar-vertical {
   bottom: 0;
   flex: none;
+  pointer-events: none;
   position: absolute;
   right: 0;
   top: 0;
@@ -74,12 +75,13 @@ a:focus {
 
 .scrollbar-button {
   background-color: black;
-  border: 1px solid #ccc;
   border-radius: 3px;
+  border: 1px solid #ccc;
   box-sizing: border-box;
   height: 50%;
   margin-right: 2px;
   opacity: 0;
+  pointer-events: auto;
   position: absolute;
   transition: opacity 100ms;
   width: 8px;