16 files declare their use of ProcessorPluginBase in Search API 8

AddHierarchy.php in src/Plugin/search_api/processor/AddHierarchy.php

AddURL.php in src/Plugin/search_api/processor/AddURL.php

AggregatedFields.php in src/Plugin/search_api/processor/AggregatedFields.php

ContentAccess.php in src/Plugin/search_api/processor/ContentAccess.php

EntityStatus.php in src/Plugin/search_api/processor/EntityStatus.php

Highlight.php in src/Plugin/search_api/processor/Highlight.php

LanguageWithFallback.php in src/Plugin/search_api/processor/LanguageWithFallback.php

NoUi.php in tests/search_api_test_no_ui/src/Plugin/search_api/processor/NoUi.php

NumberFieldBoost.php in src/Plugin/search_api/processor/NumberFieldBoost.php

RenderedItem.php in src/Plugin/search_api/processor/RenderedItem.php

ReverseEntityReferences.php in src/Plugin/search_api/processor/ReverseEntityReferences.php

RoleAccess.php in src/Plugin/search_api/processor/RoleAccess.php

RoleFilter.php in src/Plugin/search_api/processor/RoleFilter.php

SoulMate.php in tests/search_api_test_extraction/src/Plugin/search_api/processor/SoulMate.php

TestProcessor.php in tests/search_api_test/src/Plugin/search_api/processor/TestProcessor.php

TypeBoost.php in src/Plugin/search_api/processor/TypeBoost.php