Fix some hackificator odds and ends in wp-admin:

* `wp-activate.php` and `wp-admin/themes.php` don't need the closing PHP tag
* Switch single quotes for HTML attribute values to double in a few places
* Convert `include_once file.php` syntax to `include_once( 'file.php' )`
* Add access modifiers to methods/members in: `_WP_List_Table_Compat`, `Walker_Nav_Menu_Edit`, `Walker_Nav_Menu_Checklist`, `WP_Screen`, `Walker_Category_Checklist`
* `edit_user()` doesn't need to import the `$wpdb` global
* `wp_list_widgets()` doesn't need to import the `$sidebars_widgets` global
* switch/endswitch syntax is not supported in Hack
* A `<ul>` in `wp-admin/users.php` is unclosed

See #27881.


git-svn-id: https://develop.svn.wordpress.org/trunk@28500 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/revision.php

@@ -29,7 +29,7 @@ if ( ! $revision_id )
 	$revision_id = absint( $to );
 $redirect = 'edit.php';
 
-switch ( $action ) :
+switch ( $action ) {
 case 'restore' :
 	if ( ! $revision = wp_get_post_revision( $revision_id ) )
 		break;
@@ -80,7 +80,7 @@ default :
 
 	$redirect = false;
 	break;
-endswitch;
+}
 
 // Empty post_type means either malformed object found, or no valid parent was found.
 if ( ! $redirect && empty( $post->post_type ) )