Update to drupal-org-drupal 8.0.0-rc2. For more information, see https://www.drupal.org/node/2598668

vendor/symfony/validator/Tests/Mapping/Loader/constraint-mapping.yml

@@ -1,62 +0,0 @@
-namespaces:
-  custom: Symfony\Component\Validator\Tests\Fixtures\
-
-Symfony\Component\Validator\Tests\Fixtures\Entity:
-  group_sequence:
-    - Foo
-    - Entity
-
-  constraints:
-    # Custom constraint
-    - Symfony\Component\Validator\Tests\Fixtures\ConstraintA: ~
-    # Custom constraint with namespaces prefix
-    - "custom:ConstraintB": ~
-    # Callbacks
-    - Callback: validateMe
-    - Callback: validateMeStatic
-    - Callback: [Symfony\Component\Validator\Tests\Fixtures\CallbackClass, callback]
-
-  properties:
-    firstName:
-      # Constraint without value
-      - NotNull: ~
-      # Constraint with single value
-      - Range:
-          min: 3
-      # Constraint with multiple values
-      - Choice: [A, B]
-      # Constraint with child constraints
-      - All:
-          - NotNull: ~
-          - Range:
-              min: 3
-      # Option with child constraints
-      - All:
-          constraints:
-            - NotNull: ~
-            - Range:
-                min: 3
-      # Value with child constraints
-      - Collection:
-          fields:
-            foo:
-              - NotNull: ~
-              - Range:
-                  min: 3
-            bar:
-              - Range:
-                  min: 5
-      # Constraint with options
-      - Choice: { choices: [A, B], message: Must be one of %choices% }
-    dummy:
-
-  getters:
-    lastName:
-      - NotNull: ~
-    valid:
-      - "IsTrue": ~
-    permissions:
-      - "IsTrue": ~
-
-Symfony\Component\Validator\Tests\Fixtures\GroupSequenceProviderEntity:
-  group_sequence_provider: true