13 files declare their use of MapDataDefinition

ComplexDataConstraintValidatorTest.php in core/tests/Drupal/KernelTests/Core/TypedData/ComplexDataConstraintValidatorTest.php
EntityBundleExistsConstraintValidatorTest.php in core/tests/Drupal/KernelTests/Core/Entity/EntityBundleExistsConstraintValidatorTest.php
LinkItem.php in core/modules/link/src/Plugin/Field/FieldType/LinkItem.php
Map.php in core/lib/Drupal/Core/TypedData/Plugin/DataType/Map.php
MapDataNormalizerTest.php in core/modules/serialization/tests/src/Kernel/MapDataNormalizerTest.php
Mapping.php in core/lib/Drupal/Core/Config/Schema/Mapping.php
MappingTest.php in core/tests/Drupal/KernelTests/Config/Schema/MappingTest.php
RecursiveContextualValidatorTest.php in core/tests/Drupal/Tests/Core/TypedData/RecursiveContextualValidatorTest.php
TypedConfigManager.php in core/lib/Drupal/Core/Config/TypedConfigManager.php
TypedDataDefinitionTest.php in core/tests/Drupal/KernelTests/Core/TypedData/TypedDataDefinitionTest.php
TypedDataTest.php in core/tests/Drupal/KernelTests/Core/TypedData/TypedDataTest.php
ValidKeysConstraintValidator.php in core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/ValidKeysConstraintValidator.php
ValidKeysConstraintValidatorTest.php in core/tests/Drupal/KernelTests/Core/TypedData/ValidKeysConstraintValidatorTest.php

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