Revert + add test for empty string in PDO::qutoe()

Author: Girgias

ext/pdo/pdo_dbh.c

@@ -1147,11 +1147,6 @@ PHP_METHOD(PDO, quote)
 
 	PDO_CONSTRUCT_CHECK;
 
-	if (str_len == 0) {
-		zend_argument_value_error(1, "cannot be empty");
-		RETURN_THROWS();
-	}
-
 	PDO_DBH_CLEAR_ERR();
 	if (!dbh->methods->quoter) {
 		pdo_raise_impl_error(dbh, NULL, "IM001", "driver does not support quoting");

ext/pdo/tests/pdo_quote_empty_string.phpt

@@ -0,0 +1,22 @@
+--TEST--
+PDO::quote() must accept empty string
+--SKIPIF--
+<?php
+if (!extension_loaded('pdo')) die('skip');
+$dir = getenv('REDIR_TEST_DIR');
+if (false == $dir) die('skip no driver');
+require_once $dir . 'pdo_test.inc';
+PDOTest::skip();
+?>
+--FILE--
+<?php
+if (getenv('REDIR_TEST_DIR') === false) putenv('REDIR_TEST_DIR='.__DIR__ . '/../../pdo/tests/');
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+
+$pdo  = PDOTest::factory();
+
+var_dump($pdo->quote(''));
+
+?>
+--EXPECT--
+string(2) "''"