[NTP] Fix grid layout CSS override

-webkit-any does not have precedence when overriding the style.

Before: https://screenshot.googleplex.com/HXygoGNSWEA.png
After: https://screenshot.googleplex.com/kGSqb4ebEXA.png

Bug: 851335
Change-Id: Ice7db199eb08635a488a0d1d98cda0299a2a88d8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1637678
Commit-Queue: Kristi Park <kristipark@chromium.org>
Commit-Queue: Kyle Milka <kmilka@chromium.org>
Auto-Submit: Kristi Park <kristipark@chromium.org>
Reviewed-by: Kyle Milka <kmilka@chromium.org>
Cr-Commit-Position: refs/heads/master@{#664909}

chrome/browser/resources/local_ntp/most_visited_single.css

@@ -73,7 +73,8 @@ a:visited {
   user-select: none;
 }
 
-body.grid-layout :-webkit-any(#mv-tiles, .mv-tiles-old) {
+body.grid-layout #mv-tiles,
+body.grid-layout .mv-tiles-old {
   display: block;
   flex-wrap: unset;
   justify-content: unset;