Issue #2184653 by amateescu: Rename Drupal\Component\Utility\Url to UrlHelper.

core/includes/bootstrap.inc

core/includes/common.inc

core/includes/form.inc

core/includes/pager.inc

core/includes/path.inc

core/includes/tablesort.inc

core/includes/theme.inc

core/lib/Drupal/Component/Utility/UrlHelper.php

core/lib/Drupal/Component/Utility/Xss.php

core/lib/Drupal/Core/Form/ConfirmFormHelper.php

core/lib/Drupal/Core/Form/FormBuilder.php

core/lib/Drupal/Core/Routing/UrlGenerator.php

core/lib/Drupal/Core/Url.php

...les/aggregator/lib/Drupal/aggregator/Form/OpmlFeedAdd.php

core/modules/contextual/contextual.module

core/modules/field_ui/lib/Drupal/field_ui/FieldUI.php

core/modules/image/lib/Drupal/image/Entity/ImageStyle.php

...Drupal/link/Plugin/Field/FieldFormatter/LinkFormatter.php

...lib/Drupal/system/Tests/Common/RenderElementTypesTest.php

...les/system/lib/Drupal/system/Tests/Common/XssUnitTest.php