Description:
------------
When not calling closeCursor after a single line select the next statement fails without error because cursor is not closed.

Reproduce code:
---------------
The following code does not insert anything, returns 00000 for the errorCode
<?php
$db = new PDO("mysql:dbname=chatbeta;host=localhost", "chatbeta", "chatbeta");
if(!$db) {
  die("DB Connection Failed");
}
$logstmt = $db->prepare('INSERT INTO logger (login, data) VALUES (:var1, :var2)');
$authstmt = $db->prepare('SELECT * FROM users WHERE login = :varlog AND password = :varpass');
$authstmt->execute(array(':varlog' => 'testing', ':varpass' => 'testing'));
print_r($authstmt->fetch());
$logstmt->execute(array(':var1' => 'test1', ':var2' => 'test2'));
print_r($db->errorCode());
?>


The following code works, same thing 00000 returned for errorcode. Only diffrence closeCursor added.
<?php
$db = new PDO("mysql:dbname=chatbeta;host=localhost", "chatbeta", "chatbeta");
if(!$db) {
  die("DB Connection Failed");
}
$logstmt = $db->prepare('INSERT INTO logger (login, data) VALUES (:var1, :var2)');
$authstmt = $db->prepare('SELECT * FROM users WHERE login = :varlog AND password = :varpass');
$authstmt->execute(array(':varlog' => 'testing', ':varpass' => 'testing'));
print_r($authstmt->fetch());
$authstmt->closeCursor();
$logstmt->execute(array(':var1' => 'test1', ':var2' => 'test2'));
print_r($db->errorCode());
?>


There is only a single line in the users table, so only one row is returned. If I change the fetch to fetchAll it works without the closeCursor.

Expected result:
----------------
Expect an error when the insert fails due to a unclosed cursor.

Actual result:
--------------
No insert of data into the database, no error