Fixes #3098. (#7591)

Prevent devhub from showing success message when edit errors occur

static/js/zamboni/devhub.js

@@ -335,11 +335,13 @@ function addonFormSubmit() {
             parent_div.find(".item").removeClass("loaded").addClass("loading");
             var $document = $(document),
                 scrollBottom = $document.height() - $document.scrollTop(),
-                $form = $(this),
-                hasErrors = $form.find('.errorlist').length;
+                $form = $(this);
 
             $.post($form.attr('action'), $form.serialize(), function(d) {
                 parent_div.html(d).each(addonFormSubmit);
+                // The HTML has changed after we posted the form, thus the need to retrieve the new HTML
+                $form = parent_div.find('form');
+                var hasErrors = $form.find('.errorlist').length;
                 $('.tooltip').tooltip('#tooltip');
                 if (!hasErrors && old_baseurl && old_baseurl !== baseurl()) {
                     document.location = baseurl();