Themes: Introduce `theme_templates` filter for page templates of all post types.

This complements the `theme_{$post_type}_templates` dynamic filter added in [38951].

Props desrosj.
Fixes #43872.
Built from https://develop.svn.wordpress.org/trunk@43025


git-svn-id: http://core.svn.wordpress.org/trunk@42854 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/class-wp-theme.php

@@ -1182,6 +1182,19 @@ final class WP_Theme implements ArrayAccess {
 		$post_templates = $this->get_post_templates();
 		$post_templates = isset( $post_templates[ $post_type ] ) ? $post_templates[ $post_type ] : array();
 
+		/**
+		 * Filters list of page templates for a theme.
+		 *
+		 * @since 5.0.0
+		 *
+		 * @param string[]     $post_templates Array of page templates. Keys are filenames,
+		 *                                     values are translated names.
+		 * @param WP_Theme     $this           The theme object.
+		 * @param WP_Post|null $post           The post being edited, provided for context, or null.
+		 * @param string       $post_type      Post type to get the templates for.
+		 */
+		$post_templates = (array) apply_filters( 'theme_templates', $post_templates, $this, $post, $post_type );
+
 		/**
 		 * Filters list of page templates for a theme.
 		 *
@@ -1197,7 +1210,9 @@ final class WP_Theme implements ArrayAccess {
 		 * @param WP_Post|null $post           The post being edited, provided for context, or null.
 		 * @param string       $post_type      Post type to get the templates for.
 		 */
-		return (array) apply_filters( "theme_{$post_type}_templates", $post_templates, $this, $post, $post_type );
+		$post_templates = (array) apply_filters( "theme_{$post_type}_templates", $post_templates, $this, $post, $post_type );
+
+		return $post_templates;
 	}
 
 	/**

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.0-alpha-43024';
+$wp_version = '5.0-alpha-43025';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.