16 files declare their use of Field in Search API 8

AddHierarchyTest.php in tests/src/Kernel/Processor/AddHierarchyTest.php

AddURLKernelTest.php in tests/src/Kernel/Processor/AddURLKernelTest.php

FieldsHelper.php in src/Utility/FieldsHelper.php

FieldsProcessorPluginBaseTest.php in tests/src/Unit/Processor/FieldsProcessorPluginBaseTest.php

HighlightTest.php in tests/src/Unit/Processor/HighlightTest.php

HtmlFilterTest.php in tests/src/Unit/Processor/HtmlFilterTest.php

IgnoreCaseTest.php in tests/src/Unit/Processor/IgnoreCaseTest.php

IgnoreCharacterTest.php in tests/src/Unit/Processor/IgnoreCharacterTest.php

ItemFieldTest.php in tests/src/Unit/ItemFieldTest.php

LanguageWithFallbackTest.php in tests/src/Kernel/Processor/LanguageWithFallbackTest.php

ProcessorIntegrationTest.php in tests/src/Functional/ProcessorIntegrationTest.php

ProcessorTestBase.php in tests/src/Kernel/Processor/ProcessorTestBase.php

ReverseEntityReferencesTest.php in tests/src/Kernel/Processor/ReverseEntityReferencesTest.php

SerializationTest.php in tests/src/Kernel/System/SerializationTest.php

StemmerTest.php in tests/src/Unit/Processor/StemmerTest.php

TestItemsTrait.php in tests/src/Unit/Processor/TestItemsTrait.php