Don't animate the listing chooser until the page has loaded.

This should fix the collapse animation playing upon first load.

r2/r2/public/static/css/reddit.less

@@ -7074,7 +7074,10 @@ body.with-listing-chooser.listing-chooser-collapsed {
     padding-right: @listing-chooser-grippy-width;
     background: #f7f7f7;
     overflow: hidden;
-    .transition(width, .25s);
+
+    &.initialized {
+        .transition(width, .25s);
+    }
 
     &:after {
         content: '';

r2/r2/public/static/js/multi.js

@@ -492,6 +492,10 @@ r.multi.ListingChooser = Backbone.View.extend({
         'click .grippy': 'toggleCollapsed'
     },
 
+    initialize: function() {
+        this.$el.addClass('initialized')
+    },
+
     createClick: function(ev) {
         if (!this.$('.create').is('.expanded')) {
             ev.preventDefault()