Make sure WP_Customize_Manager::theme() never returns null.

* Fixes issue in [31533] that caused unit test fatal error

fixes #31445
Built from https://develop.svn.wordpress.org/trunk@31536


git-svn-id: http://core.svn.wordpress.org/trunk@31517 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/class-wp-customize-manager.php

@@ -314,6 +314,9 @@ final class WP_Customize_Manager {
 	 * @return WP_Theme
 	 */
 	public function theme() {
+		if ( ! $this->theme ) {
+			$this->theme = wp_get_theme();
+		}
 		return $this->theme;
 	}
 

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.2-alpha-31535';
+$wp_version = '4.2-alpha-31536';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.