8 string references to 'Error' in Drupal 8

drupal_error_levels in core/includes/errors.inc

Maps PHP error constants to watchdog severity levels.

RfcLogLevel::getLevels in core/lib/Drupal/Core/Logger/RfcLogLevel.php

Returns a list of severity levels, as defined in RFC 5424.

StatusReportPage::preRenderCounters in core/modules/system/src/Element/StatusReportPage.php

#pre_render callback to create counter elements.

system_requirements in core/modules/system/system.install

Implements hook_requirements().

template_preprocess_update_project_status in core/modules/update/update.report.inc

Prepares variables for update project status templates.

unicode_requirements in core/includes/unicode.inc

Moves unicode_requirements() logic to system_requirements().

update_script_test_requirements in core/modules/system/tests/modules/update_script_test/update_script_test.install

Implements hook_requirements().

_drupal_log_error in core/includes/errors.inc

Logs a PHP error or exception and displays an error page in fatal cases.