Merge branch '2.7' into 2.8

* 2.7:
  Prevent double registrations related to tag priorities

Author: fabpot

DependencyInjection/Compiler/SerializerPass.php

@@ -57,11 +57,9 @@ private function findAndSortTaggedServices($tagName, ContainerBuilder $container
         }
 
         $sortedServices = array();
-        foreach ($services as $serviceId => $tags) {
-            foreach ($tags as $attributes) {
-                $priority = isset($attributes['priority']) ? $attributes['priority'] : 0;
-                $sortedServices[$priority][] = new Reference($serviceId);
-            }
+        foreach ($services as $serviceId => $attributes) {
+            $priority = isset($attributes[0]['priority']) ? $attributes[0]['priority'] : 0;
+            $sortedServices[$priority][] = new Reference($serviceId);
         }
 
         krsort($sortedServices);

Tests/DependencyInjection/Compiler/SerializerPassTest.php

@@ -72,9 +72,9 @@ public function testThrowExceptionWhenNoEncoders()
     public function testServicesAreOrderedAccordingToPriority()
     {
         $services = array(
-            'n3' => array('tag' => array()),
-            'n1' => array('tag' => array('priority' => 200)),
-            'n2' => array('tag' => array('priority' => 100)),
+            'n3' => array(array()),
+            'n1' => array(array('priority' => 200)),
+            'n2' => array(array('priority' => 100)),
         );
 
         $expected = array(