[web_dev_style] Changing :pseudo-element to ::pseudo-element to match

chrome/browser/resources/shared/css/menu.css

Index: chrome/browser/resources/shared/css/menu.css
diff --git a/chrome/browser/resources/shared/css/menu.css b/chrome/browser/resources/shared/css/menu.css
index 60713573d238b63ecc27b6708a85ee82cb4a8eec..7188d139c605d37c0b11441c37266d9a36ff5ffa 100644
--- a/chrome/browser/resources/shared/css/menu.css
+++ b/chrome/browser/resources/shared/css/menu.css
@@ -65,7 +65,7 @@ menu > :not(hr)[selected]:active {
   color: #fff;
 }
 
-menu > [checked]:before {
+menu > [checked]::before {
   content: url('../images/checkbox_black.png');
   display: inline-block;
   height: 9px;
@@ -78,14 +78,14 @@ menu > [checked] {
   -webkit-padding-start: 0;
 }
 
-menu > [selected][checked]:active:before {
+menu > [selected][checked]:active::before {
   content: url('../images/checkbox_white.png');
 }
 
-/* TODO(zvorygin) menu > [shortcutText]:after - this selector is much better,
+/* TODO(zvorygin) menu > [shortcutText]::after - this selector is much better,
  * but it's buggy in current webkit revision, so I have to use [showShortcuts]
  */
-menu[showShortcuts] > :after {
+menu[showShortcuts] > ::after {
   -webkit-padding-start: 30px;
   color: #999;
   content: attr(shortcutText);