Files app: Fix selection background color on file list

Change the background color when the file is selected and is the lead
(currently focused) to be blue, instead of gray.

Claire approves! :-)

Bug: 968478
Change-Id: I5dc33104a7fe37abaddb5817c58f83a1c796f383
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1672612
Commit-Queue: Luciano Pacheco <lucmult@chromium.org>
Auto-Submit: Luciano Pacheco <lucmult@chromium.org>
Reviewed-by: Noel Gordon <noel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#671913}

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

@@ -1431,7 +1431,7 @@ html[dir='rtl'] .badge {
 #list-container list > li.accepts,
 #list-container list:focus > li[lead],
 #default-tasks-list > li[selected] {
-  background-color: rgb(232, 232, 232);
+  background-color: rgb(232, 234, 237);
 }
 
 #list-container list:focus > li[selected],
@@ -1441,12 +1441,12 @@ html[dir='rtl'] .badge {
   background-color: rgb(216, 223, 240);
 }
 
-body.check-select #list-container list > li[lead],
+body.check-select #list-container list > li[lead]:not([selected]),
 #list-container list > li[lead]:not([selected]) {
   background-color: rgba(232, 234, 237, 0.5);
 }
 
-body.check-select #list-container list:focus > li[lead],
+body.check-select #list-container list:focus > li[lead]:not([selected]),
 #list-container list > li[lead]:not([selected]):focus {
   background-color: rgb(232, 234, 237);
 }