[FIX] web_editor, portal: some edition fixes

- Hide navbar divider in mobile view
- Change font to default when applying header style
- Remove form tag from media dialog search input to avoid redirection

addons/portal/static/src/less/website.wrapwrap.less

@@ -191,6 +191,9 @@ hr {
         &.divider {
             .o-w-fill-navbar();
             border-right: 1px solid @navbar-default-link-disabled-color;
+            @media (max-width: @screen-xs-max) {
+                display: none;
+            }
         }
 
         &.active + .divider {

addons/web_editor/static/src/js/editor/summernote.js

@@ -1761,6 +1761,7 @@ $.summernote.pluginEvents.outdent = function (event, editor, layoutInfo) {
 };
 
 $.summernote.pluginEvents.formatBlock = function (event, editor, layoutInfo, sTagName) {
+    $.summernote.pluginEvents.applyFont(event, editor, layoutInfo, null, null, "Default");
     var $editable = layoutInfo.editable();
     $editable.data('NoteHistory').recordUndo($editable);
     event.preventDefault();

addons/web_editor/static/src/xml/editor.xml

@@ -62,12 +62,10 @@
                 </ul>
             </li>
             <li class="search">
-                <form action="#">
-                    <div class="form-group">
-                        <input class="form-control" id="icon-search" type="search"/>
-                        <span class="fa fa-search"/>
-                    </div>
-                </form>
+                <div class="form-group">
+                    <input class="form-control" id="icon-search" type="search"/>
+                    <span class="fa fa-search"/>
+                </div>
             </li>
         </ul>
         <!-- Tab panes -->