Rename the new page_templates filter to theme_page_templates, and pass it a post object for proper context.

see #13265.

Built from https://develop.svn.wordpress.org/trunk@27470


git-svn-id: http://core.svn.wordpress.org/trunk@27315 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/includes/theme.php

@@ -78,10 +78,11 @@ function delete_theme($stylesheet, $redirect = '') {
  *
  * @since 1.5.0
  *
+ * @param WP_Post|null $post Optional. The post being edited, provided for context.
  * @return array Key is the template name, value is the filename of the template
  */
-function get_page_templates() {
-	return array_flip( wp_get_theme()->get_page_templates() );
+function get_page_templates( $post = null ) {
+	return array_flip( wp_get_theme()->get_page_templates( $post ) );
 }
 
 /**