diff --git a/core/lib/Drupal/Core/TypedData/Validation/ConstraintViolationBuilder.php b/core/lib/Drupal/Core/TypedData/Validation/ConstraintViolationBuilder.php
index 59eb6e6..eb785e5 100644
--- a/core/lib/Drupal/Core/TypedData/Validation/ConstraintViolationBuilder.php
+++ b/core/lib/Drupal/Core/TypedData/Validation/ConstraintViolationBuilder.php
@@ -6,6 +6,7 @@
 use Symfony\Component\Validator\Constraint;
 use Symfony\Component\Validator\ConstraintViolation;
 use Symfony\Component\Validator\ConstraintViolationList;
+use Symfony\Component\Validator\Util\PropertyPath;
 use Symfony\Component\Validator\Violation\ConstraintViolationBuilderInterface;
 
 /**
diff --git a/core/lib/Drupal/Core/TypedData/Validation/ExecutionContext.php b/core/lib/Drupal/Core/TypedData/Validation/ExecutionContext.php
index 64968fb..da29f53 100644
--- a/core/lib/Drupal/Core/TypedData/Validation/ExecutionContext.php
+++ b/core/lib/Drupal/Core/TypedData/Validation/ExecutionContext.php
@@ -13,6 +13,7 @@
 use Symfony\Component\Validator\ConstraintViolationList;
 use Symfony\Component\Validator\Context\ExecutionContextInterface;
 use Symfony\Component\Validator\Mapping\MetadataInterface;
+use Symfony\Component\Validator\Util\PropertyPath;
 use Symfony\Component\Validator\Validator\ValidatorInterface;
 
 /**
@@ -20,7 +21,7 @@
  *
  * We do not use the context provided by Symfony as it is marked internal, so
  * this class is pretty much the same, but has some code style changes as well
- * as execeptions for methods we don't support.
+ * as exceptions for methods we don't support.
  */
 class ExecutionContext implements ExecutionContextInterface {
 
diff --git a/core/lib/Drupal/Core/TypedData/Validation/RecursiveContextualValidator.php b/core/lib/Drupal/Core/TypedData/Validation/RecursiveContextualValidator.php
index 13a212e..fe77434 100644
--- a/core/lib/Drupal/Core/TypedData/Validation/RecursiveContextualValidator.php
+++ b/core/lib/Drupal/Core/TypedData/Validation/RecursiveContextualValidator.php
@@ -15,6 +15,7 @@
 use Symfony\Component\Validator\ConstraintValidatorFactoryInterface;
 use Symfony\Component\Validator\Context\ExecutionContextInterface;
 use Symfony\Component\Validator\Mapping\Factory\MetadataFactoryInterface;
+use Symfony\Component\Validator\Util\PropertyPath;
 
 /**
  * Defines a recursive contextual validator for Typed Data.
@@ -22,6 +23,12 @@
  * For both list and complex data it call recursively out to the properties /
  * elements of the list.
  *
+ * This class calls out to a couple of methods on the context marked as
+ * internally. Those are internally for the validator (which is implemented by
+ * this class) but should not be called by users.
+ * See http://symfony.com/doc/current/contributing/code/bc.html for more
+ * information about @internal.
+ *
  * @see \Drupal\Core\TypedData\Validation\RecursiveValidator::startContext()
  * @see \Drupal\Core\TypedData\Validation\RecursiveValidator::inContext()
  */
@@ -156,6 +163,11 @@ protected function validateNode(TypedDataInterface $data, $constraints = NULL, $
    *
    * @param mixed $value
    *   The validated value.
+   * @param string $cache_key
+   *   The cache key used internally to ensure we don't validate the same
+   *   constraint twice.
+   * @param \Symfony\Component\Validator\Constraint[] $constraints
+   *   The constraints which should be ensured for the given value.
    */
   protected function validateConstraints($value, $cache_key, $constraints) {
     foreach ($constraints as $constraint) {
diff --git a/core/lib/Drupal/Core/TypedData/Validation/TypedDataAwareValidatorTrait.php b/core/lib/Drupal/Core/TypedData/Validation/TypedDataAwareValidatorTrait.php
index b590f2f..7c0509f 100644
--- a/core/lib/Drupal/Core/TypedData/Validation/TypedDataAwareValidatorTrait.php
+++ b/core/lib/Drupal/Core/TypedData/Validation/TypedDataAwareValidatorTrait.php
@@ -7,7 +7,6 @@
 
 namespace Drupal\Core\TypedData\Validation;
 
-use Drupal\Core\TypedData\PrimitiveInterface;
 use Drupal\Core\TypedData\TypedDataInterface;
 
 /**
diff --git a/core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/ComplexDataConstraintValidator.php b/core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/ComplexDataConstraintValidator.php
index 94a522e..eacfcec 100755
--- a/core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/ComplexDataConstraintValidator.php
+++ b/core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/ComplexDataConstraintValidator.php
@@ -10,7 +10,6 @@
 use Drupal\Core\TypedData\ComplexDataInterface;
 use Drupal\Core\TypedData\TypedDataInterface;
 use Drupal\Core\TypedData\Validation\TypedDataAwareValidatorTrait;
-use Drupal\Core\TypedData\Validation\TypedDataPropertyValidationEnvelope;
 use Symfony\Component\Validator\Constraint;
 use Symfony\Component\Validator\ConstraintValidator;
 use Symfony\Component\Validator\Exception\UnexpectedTypeException;