11 files declare their use of Condition in Zircon Profile 8.0

AliasStorage.php in core/lib/Drupal/Core/Path/AliasStorage.php

Contains \Drupal\Core\Path\AliasStorage.

Condition.php in core/lib/Drupal/Core/Entity/Query/Sql/Condition.php

Contains \Drupal\Core\Entity\Query\Sql\Condition.

ConditionAggregate.php in core/lib/Drupal/Core/Entity/Query/Sql/ConditionAggregate.php

Contains \Drupal\Core\Entity\Query\Sql\ConditionAggregate.

ConditionTest.php in core/tests/Drupal/Tests/Core/Database/ConditionTest.php

Contains \Drupal\Tests\Core\Database\ConditionTest.

database.inc in core/includes/database.inc

Core systems for the database layer.

File.php in core/modules/file/src/Plugin/migrate/source/d7/File.php

Contains \Drupal\file\Plugin\migrate\source\d7\File.

NodeGrantDatabaseStorage.php in core/modules/node/src/NodeGrantDatabaseStorage.php

Contains \Drupal\node\NodeGrantDatabaseStorage.

NodeSearch.php in core/modules/node/src/Plugin/Search/NodeSearch.php

Contains \Drupal\node\Plugin\Search\NodeSearch.

Schema.php in core/lib/Drupal/Core/Database/Schema.php

Contains \Drupal\Core\Database\Schema.

Schema.php in core/lib/Drupal/Core/Database/Driver/mysql/Schema.php

Contains \Drupal\Core\Database\Driver\mysql\Schema.

ViewsSearchQuery.php in core/modules/search/src/ViewsSearchQuery.php

Contains \Drupal\search\ViewsSearchQuery.