15 files declare their use of AccountProxyInterface

AccessPolicyProcessorTest.php in core/tests/Drupal/Tests/Core/Session/AccessPolicyProcessorTest.php
AuthenticationSubscriber.php in core/lib/Drupal/Core/EventSubscriber/AuthenticationSubscriber.php
FormBuilderTest.php in core/tests/Drupal/Tests/Core/Form/FormBuilderTest.php
LinkAccessConstraintValidator.php in core/modules/link/src/Plugin/Validation/Constraint/LinkAccessConstraintValidator.php
PrivateTempStore.php in core/lib/Drupal/Core/TempStore/PrivateTempStore.php
PrivateTempStoreFactory.php in core/lib/Drupal/Core/TempStore/PrivateTempStoreFactory.php
ProtectedUserFieldConstraintValidator.php in core/modules/user/src/Plugin/Validation/Constraint/ProtectedUserFieldConstraintValidator.php
SharedTempStore.php in core/lib/Drupal/Core/TempStore/SharedTempStore.php
SharedTempStoreFactory.php in core/lib/Drupal/Core/TempStore/SharedTempStoreFactory.php
SharedTempStoreTest.php in core/tests/Drupal/Tests/Core/TempStore/SharedTempStoreTest.php
TempStoreDatabaseTest.php in core/tests/Drupal/KernelTests/Core/TempStore/TempStoreDatabaseTest.php
ToolbarLinkBuilder.php in core/modules/user/src/ToolbarLinkBuilder.php
ToolbarLinkBuilderTest.php in core/modules/user/tests/src/Unit/ToolbarLinkBuilderTest.php
UserLazyBuilder.php in core/modules/navigation/src/UserLazyBuilder.php
WorkspaceManager.php in core/modules/workspaces/src/WorkspaceManager.php

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