feat: add frontend-plugin-framework slots (#545)

Add the following `frontend-plugin-framework` slots:
* `logo_slot`
* `desktop_main_menu_slot`
* `desktop_secondary_menu_slot`
* `mobile_main_menu_slot`
* `course_info_slot`
* `learning_help_slot`
* `desktop_logged_out_items_slot`
* `mobile_logged_out_items_slot`
* `mobile_user_menu_slot`
* `desktop_user_menu_slot`
* `learning_user_menu_slot`
* `learning_logged_out_items_slot`
* `desktop_header_slot`

src/mobile-header/MobileHeaderMainMenu.jsx

@@ -0,0 +1,58 @@
+import React from 'react';
+import PropTypes from 'prop-types';
+
+import { Menu, MenuTrigger, MenuContent } from '../Menu';
+
+const MobileHeaderMainMenu = ({ menu }) => {
+  // Nodes are accepted as a prop
+  if (!Array.isArray(menu)) {
+    return menu;
+  }
+
+  return menu.map((menuItem) => {
+    const {
+      type,
+      href,
+      content,
+      submenuContent,
+      disabled,
+      isActive,
+      onClick,
+    } = menuItem;
+
+    if (type === 'item') {
+      return (
+        <a
+          key={`${type}-${content}`}
+          className={`nav-link${disabled ? ' disabled' : ''}${isActive ? ' active' : ''}`}
+          href={href}
+          onClick={onClick || null}
+        >
+          {content}
+        </a>
+      );
+    }
+
+    return (
+      <Menu key={`${type}-${content}`} tag="div" className="nav-item">
+        <MenuTrigger onClick={onClick || null} tag="a" role="button" tabIndex="0" className="nav-link">
+          {content}
+        </MenuTrigger>
+        <MenuContent className="position-static pin-left pin-right py-2">
+          {submenuContent}
+        </MenuContent>
+      </Menu>
+    );
+  });
+};
+
+export const mobileHeaderMainMenuDataShape = PropTypes.oneOfType([
+  PropTypes.node,
+  PropTypes.array,
+]);
+
+MobileHeaderMainMenu.propTypes = {
+  menu: mobileHeaderMainMenuDataShape,
+};
+
+export default MobileHeaderMainMenu;