14 files declare their use of LinkItemInterface
- LinkFieldTest.php in core/
modules/ link/ tests/ src/ Functional/ LinkFieldTest.php  - LinkFieldUITest.php in core/
modules/ link/ tests/ src/ Functional/ LinkFieldUITest.php  - LinkFormatter.php in core/
modules/ link/ src/ Plugin/ Field/ FieldFormatter/ LinkFormatter.php  - LinkFormatterTest.php in core/
modules/ link/ tests/ src/ Unit/ LinkFormatterTest.php  - LinkItem.php in core/
modules/ link/ src/ Plugin/ Field/ FieldType/ LinkItem.php  - LinkItemSerializationTest.php in core/
modules/ link/ tests/ src/ Kernel/ LinkItemSerializationTest.php  - LinkItemTest.php in core/
modules/ link/ tests/ src/ Kernel/ LinkItemTest.php  - LinkTypeConstraintValidator.php in core/
modules/ link/ src/ Plugin/ Validation/ Constraint/ LinkTypeConstraintValidator.php  - LinkWidget.php in core/
modules/ link/ src/ Plugin/ Field/ FieldWidget/ LinkWidget.php  - link_test_base_field.module in core/
modules/ link/ tests/ modules/ link_test_base_field/ link_test_base_field.module  - Contains main module functions.
 - MenuLinkContent.php in core/
modules/ menu_link_content/ src/ Entity/ MenuLinkContent.php  - MigrateFieldInstanceTest.php in core/
modules/ field/ tests/ src/ Kernel/ Migrate/ d6/ MigrateFieldInstanceTest.php  - RouteCachingLanguageTest.php in core/
tests/ Drupal/ FunctionalTests/ Routing/ RouteCachingLanguageTest.php  - Shortcut.php in core/
modules/ shortcut/ src/ Entity/ Shortcut.php  
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