[REF] web: FormRenderer: extract _renderHeaderButtons

... function to ease extensions and overrides (especially, an
override in web_enterprise).

addons/web/static/src/js/views/form/form_renderer.js

@@ -315,6 +315,21 @@ var FormRenderer = BasicRenderer.extend({
         this._registerModifiers(node, this.state, $button);
         return $button;
     },
+    /**
+     * @private
+     * @param {Object} node
+     * @returns {jQueryElement}
+     */
+    _renderHeaderButtons: function (node) {
+        var self = this;
+        var $buttons = $('<div>', {class: 'o_statusbar_buttons'});
+        _.each(node.children, function (child) {
+            if (child.tag === 'button') {
+                $buttons.append(self._renderHeaderButton(child));
+            }
+        });
+        return $buttons;
+    },
     /**
      * @private
      * @param {Object} node
@@ -578,12 +593,9 @@ var FormRenderer = BasicRenderer.extend({
     _renderTagHeader: function (node) {
         var self = this;
         var $statusbar = $('<div>', {class: 'o_form_statusbar'});
-        var $buttons = $('<div>', {class: 'o_statusbar_buttons'});
-        $statusbar.append($buttons);
+        $statusbar.append(this._renderHeaderButtons(node));
         _.each(node.children, function (child) {
-            if (child.tag === 'button') {
-                $buttons.append(self._renderHeaderButton(child));
-            } else if (child.tag === 'field') {
+            if (child.tag === 'field') {
                 var widget = self._renderFieldWidget(child, self.state);
                 $statusbar.append(widget.$el);
             }