Reduce webkit CSS prefixes in ui/ styles

ui/file_manager/file_manager/foreground/js/ui/file_grid.js

Index: ui/file_manager/file_manager/foreground/js/ui/file_grid.js
diff --git a/ui/file_manager/file_manager/foreground/js/ui/file_grid.js b/ui/file_manager/file_manager/foreground/js/ui/file_grid.js
index dca897ed31fb592c1831a8fce458d9320ff32790..e154cdbb5ed4387ade9af2883400a075b4ca5c4d 100644
--- a/ui/file_manager/file_manager/foreground/js/ui/file_grid.js
+++ b/ui/file_manager/file_manager/foreground/js/ui/file_grid.js
@@ -684,7 +684,7 @@ FileGrid.setThumbnailImage_ = function(
     thumbnail.style.backgroundSize = 'cover';
 
   thumbnail.style.backgroundImage = 'url(' + dataUrl + ')';
-  thumbnail.addEventListener('webkitAnimationEnd', function() {
+  thumbnail.addEventListener('animationend', function() {
     // Remove animation css once animation is completed in order not to animate
     // again when an item is attached to the dom again.
     thumbnail.classList.remove('animate');