Files.app: Add focus feedback on dialog footer.

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 005768ed69add0095cb9349e06113e33cfd89fae..af7c0a6532b8a46c509babb488e1008aafbff479 100644
--- a/ui/file_manager/file_manager/foreground/css/file_manager.css
+++ b/ui/file_manager/file_manager/foreground/css/file_manager.css
@@ -674,7 +674,7 @@ body.selecting #search-box {
   background: transparent;
   border: 0;
   border-image: none;
-  border-radius: 3px;
+  border-radius: 2px;
   box-sizing: border-box;
   cursor: pointer;
   margin: 0 0.29em;
@@ -754,6 +754,13 @@ body.selecting #search-box {
   border-image: none;
 }
 
+/* Draw outline using box-shadow to make them rounded. */
+.dialog-footer .primary:focus,
+.dialog-footer .secondary:focus,
+.dialog-footer select:focus {
+  box-shadow: 0 0 0 2px rgba(27, 168, 243, 0.5);
+}
+
 .progressable:not([progress]) .progress-bar,
 .progressable:not([progress]) .preparing-label {
   display: none;