Mysqli: fix missing error for invalid mysqli_options() option

ext/mysqli/mysqli_api.c

@@ -1209,6 +1209,10 @@ PHP_FUNCTION(mysqli_options)
 				convert_to_long(mysql_value);
 				break;
 			default:
+				if (MyG(report_mode) & MYSQLI_REPORT_ERROR) {
+					zend_value_error("mysqli_options(): Invalid option %d", (int)mysql_option);
+				}
+				ret = 1;
 				break;
 		}
 	}

ext/mysqli/tests/gh20968.phpt

@@ -0,0 +1,36 @@
+--TEST--
+Bug #20968 mysqli_options() with invalid option triggers ValueError
+--EXTENSIONS--
+mysqli
+--CONFLICTS--
+mysqli
+--SKIPIF--
+<?php
+require_once 'skipifconnectfailure.inc';
+?>
+--FILE--
+<?php
+require_once 'connect.inc';
+
+$driver = new mysqli_driver();
+
+$mysqli = new mysqli($host, $user, $passwd, $db, $port, $socket);
+
+$driver->report_mode = MYSQLI_REPORT_OFF;
+$value = $mysqli->options(10, 'invalid_option');
+
+var_dump($value);
+
+$driver->report_mode = MYSQLI_REPORT_ALL;
+$value = $mysqli->options(10, 'invalid_option');
+var_dump($value);
+
+?>
+--EXPECTF--
+bool(false)
+
+Fatal error: Uncaught ValueError: mysqli_options(): Invalid option %d in %s:%d
+Stack trace:
+#0 %s(%d): mysqli->options(%d, 'invalid_option')
+#1 {main}
+  thrown in %s on line %d

ext/mysqli/tests/mysqli_options.phpt

@@ -81,8 +81,6 @@ try {
     echo $e->getMessage() . "\n";
 }
 
-// invalid options do not generate errors
-mysqli_options($link, -1, "Invalid option");
 
 print "done!";
 ?>