Add missing doc blocks to wp-admin/includes/*.

Fix some egregious uses of tabbing.
Some functions can simply return `apply_filters(...)` instead of setting a variable that is immediately returned.

See #32444.


git-svn-id: https://develop.svn.wordpress.org/trunk@32654 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/includes/theme-install.php

@@ -50,6 +50,8 @@ function install_themes_feature_list() {
  * Display search form for searching themes.
  *
  * @since 2.8.0
+ *
+ * @param bool $type_selector
  */
 function install_theme_search_form( $type_selector = true ) {
 	$type = isset( $_REQUEST['type'] ) ? wp_unslash( $_REQUEST['type'] ) : 'term';
@@ -150,6 +152,8 @@ function install_themes_upload() {
  * @deprecated 3.4.0
  *
  * @global WP_Theme_Install_List_Table $wp_list_table
+ *
+ * @param object $theme
  */
 function display_theme( $theme ) {
 	_deprecated_function( __FUNCTION__, '3.4' );