Revert "wpaint.js: actually fix that"

This reverts commit b564269692.

js/wpaint.js

@@ -87,7 +87,7 @@ oekaki.init = function() {
       });
 
 
-      $("#wpaintdiv input").on("keydown", function(e) { if (e.keycode == 13) { e.preventDefault(); e.stopPropagation(); } });
+      $("#wpaintdiv input").on("keydown", function(e) { if (e.keycode == 13) e.preventDefault(); });
       $('#wpaintctr .ui-resizable-se').css({'height':'12px', 'width':'12px'});
     }
   });