10 files declare their use of RouteWrapper in Drupal 7 to 8/9 Module Upgrader 8

ContentRoute.php in src/Plugin/DMU/Routing/ContentRoute.php

FormRoute.php in src/Plugin/DMU/Routing/FormRoute.php

HookMenu.php in src/Routing/HookMenu.php

LinkBinding.php in src/Routing/LinkBinding/LinkBinding.php

LinkBindingFactory.php in src/Routing/LinkBinding/LinkBindingFactory.php

LinkBindingTest.php in tests/src/Unit/Routing/LinkBinding/LinkBindingTest.php

LocalTaskLinkBinding.php in src/Routing/LinkBinding/LocalTaskLinkBinding.php

RouteConverterInterface.php in src/Routing/RouteConverterInterface.php

RouterTest.php in tests/src/Unit/Routing/Drupal7/RouterTest.php

RouteWrapperTest.php in tests/src/Unit/Routing/Drupal7/RouteWrapperTest.php