Fixed submit handlers not being executed on modal form

This is a regression from the #5312, submitting form with jQuery
doesn't run event handlers that are attached with `addEventListener`,
e.g Django's `filter_horizontal` field.

Ref: #5590

CHANGELOG.txt

@@ -8,11 +8,6 @@
 * Changed cache-busting implementation, it is now handled by a path change,
   not by GET parameter.
 * Added a possibility to copy pages in the Page Tree by drag'n'drop.
-* Fixed a bug where it wasn't possible to scroll the toolbar menu if scroll
-  started on the disabled menu item on small screens.
-* Fixed a regression when standalone CMS Widgets wouldn't work due to
-  non-existing JavaScript dependencies.
-* Fixed a possible recursion error when using the ``Alias`` plugin.
 * Make it possible to use multi-table inheritance for Page/Title extensions.
 * Refactored plugin rendering functionality to speed up loading time in both
   structure and content mode.
@@ -23,6 +18,11 @@
 * Fixed a bug where it wasn't possible to scroll the toolbar menu if scroll
   started on the disabled menu item on small screens.
 * Fixed a migration error (0014) that occurred under certain environments.
+* Fixed a regression when standalone CMS Widgets wouldn't work due to
+  non-existing JavaScript dependencies.
+* Fixed a possible recursion error when using the ``Alias`` plugin.
+* Fixed a regression where submit handlers for modal form wouldn't be executed
+  under certain circumstances
 
 
 === 3.3.1 (2016-07-13) ===

cms/static/cms/js/modules/cms.modal.js

@@ -802,7 +802,20 @@ var Modal = new Class({
                         // as we are inside an iframe and magic is happening
                         item[0].click();
                     } else {
-                        frm.submit();
+                        // have to dispatch native submit event so all the submit handlers
+                        // can be fired, see #5590
+                        var evt = document.createEvent('HTMLEvents');
+
+                        evt.initEvent('submit', false, true);
+                        if (frm[0].dispatchEvent(evt)) {
+                            // triggering submit event in webkit based browsers won't
+                            // actually submit the form, while in Gecko-based ones it
+                            // will and calling frm.submit() would throw NS_ERROR_UNEXPECTED
+                            try {
+                                frm[0].submit();
+                            } catch (err) {
+                            }
+                        }
                     }
                 }
 

cms/templates/cms/wizards/create.html

@@ -19,7 +19,7 @@ <h1>{% trans "Create" %} {{ wizard_entry.title }}</h1>
             {% include "cms/wizards/includes/form_fields.html" %}
         </div>
         <div class="submit-row">
-            <input type="submit" class="cms-btn cms-btn-action" value="{% trans "Create" %}">
+            <input type="submit" class="default cms-btn cms-btn-action" value="{% trans "Create" %}">
             <button type="submit" name="wizard_goto_step"
                 class="cms-btn cms-btn-secondary cms-btn-group" value="{{ wizard.steps.prev }}">
                 {% trans "Back" %}

cms/templates/cms/wizards/start.html

@@ -27,7 +27,7 @@ <h1>{% trans "Create" %}</h1>
             {% endfor %}
         </div>
         <div class="submit-row">
-            <input type="submit" value="{% trans 'Next' %}" class="cms-btn cms-btn-action" name="_continue">
+            <input type="submit" value="{% trans 'Next' %}" class="default cms-btn cms-btn-action" name="_continue">
         </div>
     </form>
 {% endblock %}