fixed test

tests/Symfony/Tests/Component/Form/Extension/Csrf/CsrfProvider/SessionCsrfProviderTest.php

@@ -31,9 +31,6 @@ class SessionCsrfProviderTest extends \PHPUnit_Framework_TestCase
 
     public function testGenerateCsrfToken()
     {
-        $this->session->expects($this->once())
-                ->method('start');
-
         $this->session->expects($this->once())
                 ->method('getId')
                 ->will($this->returnValue('ABCDEF'));
@@ -45,9 +42,6 @@ class SessionCsrfProviderTest extends \PHPUnit_Framework_TestCase
 
     public function testIsCsrfTokenValidSucceeds()
     {
-        $this->session->expects($this->once())
-                ->method('start');
-
         $this->session->expects($this->once())
                 ->method('getId')
                 ->will($this->returnValue('ABCDEF'));
@@ -59,9 +53,6 @@ class SessionCsrfProviderTest extends \PHPUnit_Framework_TestCase
 
     public function testIsCsrfTokenValidFails()
     {
-        $this->session->expects($this->once())
-                ->method('start');
-
         $this->session->expects($this->once())
                 ->method('getId')
                 ->will($this->returnValue('ABCDEF'));