Upgrade/Install: When creating the .htaccess file in insert_with_markers(), make sure it has 0644 as a minimum set of permissions.

Props rcutmore, dd32, i3anaan.
Fixes #40572.
Built from https://develop.svn.wordpress.org/trunk@47005


git-svn-id: http://core.svn.wordpress.org/trunk@46805 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/includes/misc.php

@@ -111,9 +111,16 @@ function insert_with_markers( $filename, $marker, $insertion ) {
 		if ( ! is_writable( dirname( $filename ) ) ) {
 			return false;
 		}
+
 		if ( ! touch( $filename ) ) {
 			return false;
 		}
+
+		// Make sure the file is created with a minimum set of permissions.
+		$perms = fileperms( $filename );
+		if ( $perms ) {
+			chmod( $filename, $perms | 0644 );
+		}
 	} elseif ( ! is_writeable( $filename ) ) {
 		return false;
 	}