18 files declare their use of MenuTreeParameters

AdminTest.php in core/modules/system/tests/src/Functional/System/AdminTest.php
DisplayPageTest.php in core/modules/views/tests/src/Kernel/Plugin/DisplayPageTest.php
DisplayPathTest.php in core/modules/views_ui/tests/src/Functional/DisplayPathTest.php
MenuForm.php in core/modules/menu_ui/src/MenuForm.php
MenuLinkContentCacheabilityBubblingTest.php in core/modules/menu_link_content/tests/src/Kernel/MenuLinkContentCacheabilityBubblingTest.php
MenuLinkContentDeriverTest.php in core/modules/menu_link_content/tests/src/Kernel/MenuLinkContentDeriverTest.php
MenuLinkDefaultIntegrationTest.php in core/tests/Drupal/KernelTests/Core/Menu/MenuLinkDefaultIntegrationTest.php
MenuLinksTest.php in core/modules/menu_link_content/tests/src/Kernel/MenuLinksTest.php
MenuLinkTreeTest.php in core/tests/Drupal/KernelTests/Core/Menu/MenuLinkTreeTest.php
MenuTreeParametersTest.php in core/tests/Drupal/Tests/Core/Menu/MenuTreeParametersTest.php
MenuTreeStorageTest.php in core/tests/Drupal/KernelTests/Core/Menu/MenuTreeStorageTest.php
MigrateMenuLinkTest.php in core/modules/menu_link_content/tests/src/Kernel/Migrate/d7/MigrateMenuLinkTest.php
PathAliasMenuLinkContentTest.php in core/modules/menu_link_content/tests/src/Kernel/PathAliasMenuLinkContentTest.php
system.module in core/modules/system/system.module
Configuration system that lets administrators modify the workings of the site.
SystemController.php in core/modules/system/src/Controller/SystemController.php
SystemManager.php in core/modules/system/src/SystemManager.php
SystemMenuBlock.php in core/modules/system/src/Plugin/Block/SystemMenuBlock.php
ToolbarController.php in core/modules/toolbar/src/Controller/ToolbarController.php

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