minor symfony#9148 [Security] set allow_if_all_abstain to false (xabbuh)

This PR was merged into the 2.7 branch.

Discussion
----------

[Security] set allow_if_all_abstain to false

Commits
-------

f8e82b9 set allow_if_all_abstain to false

Author: javiereguiluz

security/voters.rst

@@ -266,7 +266,7 @@ security configuration:
         security:
             access_decision_manager:
                 strategy: unanimous
-                allow_if_all_abstain: true
+                allow_if_all_abstain: false
 
     .. code-block:: xml
 
@@ -280,7 +280,7 @@ security configuration:
         >
 
             <config>
-                <access-decision-manager strategy="unanimous" allow-if-all-abstain="true"  />
+                <access-decision-manager strategy="unanimous" allow-if-all-abstain="false"  />
             </config>
         </srv:container>
 
@@ -290,6 +290,6 @@ security configuration:
         $container->loadFromExtension('security', array(
             'access_decision_manager' => array(
                 'strategy' => 'unanimous',
-                'allow_if_all_abstain' => true,
+                'allow_if_all_abstain' => false,
             ),
         ));