1 files changed, 1 insertions, 4 deletions
diff --git a/chromium/ui/webui/resources/js/cr/event_target.js b/chromium/ui/webui/resources/js/cr/event_target.js
index 5bcb41d6138..d9bc681c75f 100644
--- a/chromium/ui/webui/resources/js/cr/event_target.js
+++ b/chromium/ui/webui/resources/js/cr/event_target.js
@@ -76,9 +76,6 @@ cr.define('cr', function() {
       event.__defineGetter__('target', function() {
         return self;
       });
-      event.preventDefault = function() {
-        this.returnValue = false;
-      };
 
       var type = event.type;
       var prevented = 0;
@@ -93,7 +90,7 @@ cr.define('cr', function() {
         }
       }
 
-      return !prevented && event.returnValue;
+      return !prevented && !event.defaultPrevented;
     }
   };