16 files declare their use of RfcLogLevel
- AreaDisplayLinkTest.php in core/
modules/ views/ tests/ src/ Kernel/ Handler/ AreaDisplayLinkTest.php  - BigPipeTest.php in core/
modules/ big_pipe/ tests/ src/ Functional/ BigPipeTest.php  - bootstrap.inc in core/
includes/ bootstrap.inc  - Functions that need to be loaded on every Drupal request.
 - dblog.admin.inc in core/
modules/ dblog/ dblog.admin.inc  - Administrative page callbacks for the Database Logging module.
 - DbLogController.php in core/
modules/ dblog/ src/ Controller/ DbLogController.php  - DbLogTest.php in core/
modules/ dblog/ tests/ src/ Functional/ DbLogTest.php  - EntityReferenceSettingsTest.php in core/
modules/ field/ tests/ src/ Kernel/ EntityReference/ EntityReferenceSettingsTest.php  - errors.inc in core/
includes/ errors.inc  - Functions for error handling.
 - FakeLogEntries.php in core/
modules/ dblog/ tests/ src/ Functional/ FakeLogEntries.php  - InstallUninstallTest.php in core/
modules/ system/ tests/ src/ Functional/ Module/ InstallUninstallTest.php  - MigrateMessage.php in core/
modules/ migrate/ src/ MigrateMessage.php  - ModuleTestBase.php in core/
modules/ system/ tests/ src/ Functional/ Module/ ModuleTestBase.php  - ProviderRepositoryTest.php in core/
modules/ media/ tests/ src/ Unit/ ProviderRepositoryTest.php  - responsive_image.module in core/
modules/ responsive_image/ responsive_image.module  - Responsive image display formatter for image fields.
 - SecurityAdvisoriesFetcherTest.php in core/
modules/ system/ tests/ src/ Kernel/ SecurityAdvisories/ SecurityAdvisoriesFetcherTest.php  - ViewsIntegrationTest.php in core/
modules/ dblog/ tests/ src/ Kernel/ Views/ ViewsIntegrationTest.php  
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