8 files declare their use of TypedDataInternalPropertiesHelper

ComplexDataNormalizer.php in core/modules/serialization/src/Normalizer/ComplexDataNormalizer.php
ContentEntityNormalizer.php in core/modules/serialization/src/Normalizer/ContentEntityNormalizer.php
ContentEntityNormalizer.php in core/modules/hal/src/Normalizer/ContentEntityNormalizer.php
FieldItemNormalizer.php in core/modules/jsonapi/src/Normalizer/FieldItemNormalizer.php
FieldItemNormalizer.php in core/modules/hal/src/Normalizer/FieldItemNormalizer.php
ResourceIdentifier.php in core/modules/jsonapi/src/JsonApiResource/ResourceIdentifier.php
ResourceObject.php in core/modules/jsonapi/src/JsonApiResource/ResourceObject.php
ResourceTestBase.php in core/modules/jsonapi/tests/src/Functional/ResourceTestBase.php

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