Merge branch '2.8' into 3.0

* 2.8:
  [HttpKernel] fixed internal subrequests having an if-modified-since-header
  [Security] Fix deprecated usage of DigestAuthenticationEntryPoint::getKey() in DigestAuthenticationListener
  [Validator] Added additional MasterCard range to the CardSchemeValidator
  Make the exception message more clear.
  [Form] fixed bug - name in ButtonBuilder
  [DoctrineBridge] added missing error code for constraint.
  [ClassLoader] Fix declared classes being computed when not needed
  [varDumper] Fix missing usage of ExceptionCaster::$traceArgs

Conflicts:
	src/Symfony/Bridge/Doctrine/Validator/Constraints/UniqueEntityValidator.php
	src/Symfony/Component/ClassLoader/ClassCollectionLoader.php

Author: nicolas-grekas

Tests/Validator/Constraints/UniqueEntityValidatorTest.php

@@ -161,6 +161,7 @@ public function testValidateUniqueness()
         $this->buildViolation('myMessage')
             ->atPath('property.path.name')
             ->setInvalidValue('Foo')
+            ->setCode(UniqueEntity::NOT_UNIQUE_ERROR)
             ->assertRaised();
     }
 
@@ -184,6 +185,7 @@ public function testValidateCustomErrorPath()
         $this->buildViolation('myMessage')
             ->atPath('property.path.bar')
             ->setInvalidValue('Foo')
+            ->setCode(UniqueEntity::NOT_UNIQUE_ERROR)
             ->assertRaised();
     }
 
@@ -235,6 +237,7 @@ public function testValidateUniquenessWithIgnoreNull()
         $this->buildViolation('myMessage')
             ->atPath('property.path.name')
             ->setInvalidValue('Foo')
+            ->setCode(UniqueEntity::NOT_UNIQUE_ERROR)
             ->assertRaised();
     }
 
@@ -266,6 +269,7 @@ public function testValidateUniquenessWithValidCustomErrorPath()
         $this->buildViolation('myMessage')
             ->atPath('property.path.name2')
             ->setInvalidValue('Bar')
+            ->setCode(UniqueEntity::NOT_UNIQUE_ERROR)
             ->assertRaised();
     }
 
@@ -398,6 +402,7 @@ public function testAssociatedEntity()
         $this->buildViolation('myMessage')
             ->atPath('property.path.single')
             ->setInvalidValue($entity1)
+            ->setCode(UniqueEntity::NOT_UNIQUE_ERROR)
             ->assertRaised();
     }
 

Validator/Constraints/UniqueEntity.php

@@ -23,6 +23,8 @@
  */
 class UniqueEntity extends Constraint
 {
+    const NOT_UNIQUE_ERROR = '23bd9dbf-6b9b-41cd-a99e-4844bcf3077f';
+
     public $message = 'This value is already used.';
     public $service = 'doctrine.orm.validator.unique';
     public $em = null;
@@ -31,6 +33,10 @@ class UniqueEntity extends Constraint
     public $errorPath = null;
     public $ignoreNull = true;
 
+    protected static $errorNames = array(
+        self::NOT_UNIQUE_ERROR => 'NOT_UNIQUE_ERROR',
+    );
+
     public function getRequiredOptions()
     {
         return array('fields');

Validator/Constraints/UniqueEntityValidator.php

@@ -130,6 +130,7 @@ public function validate($entity, Constraint $constraint)
         $this->context->buildViolation($constraint->message)
             ->atPath($errorPath)
             ->setInvalidValue($invalidValue)
+            ->setCode(UniqueEntity::NOT_UNIQUE_ERROR)
             ->addViolation();
     }
 }