50 files declare their use of Unicode

Block.php in core/modules/views/src/Plugin/views/display/Block.php
BookManager.php in core/modules/book/src/BookManager.php
CommentAdminOverview.php in core/modules/comment/src/Form/CommentAdminOverview.php
CommentAdminTest.php in core/modules/comment/tests/src/Functional/Views/CommentAdminTest.php
CommentForm.php in core/modules/comment/src/CommentForm.php
CommentPermalinkFormatter.php in core/modules/comment/src/Plugin/Field/FieldFormatter/CommentPermalinkFormatter.php
CommentTestTrait.php in core/modules/comment/src/Tests/CommentTestTrait.php
CssOptimizer.php in core/lib/Drupal/Core/Asset/CssOptimizer.php
DateTestBase.php in core/modules/datetime/tests/src/Functional/DateTestBase.php
DbLogController.php in core/modules/dblog/src/Controller/DbLogController.php
DbLogTest.php in core/modules/dblog/tests/src/Functional/DbLogTest.php
DependencyTest.php in core/modules/system/tests/src/Functional/Module/DependencyTest.php
DisplayExtenderTest.php in core/modules/views/tests/modules/views_test_data/src/Plugin/views/display_extender/DisplayExtenderTest.php
DisplayPluginBase.php in core/modules/views/src/Plugin/views/display/DisplayPluginBase.php
DisplayTest.php in core/modules/views_ui/tests/src/Functional/DisplayTest.php
DisplayTest.php in core/modules/views/tests/modules/views_test_data/src/Plugin/views/display/DisplayTest.php
ExceptionHandler.php in core/modules/mysql/src/Driver/Database/mysql/ExceptionHandler.php
FileSystem.php in core/lib/Drupal/Core/File/FileSystem.php
filter.module in core/modules/filter/filter.module
Framework for handling the filtering of content.
HandlerBase.php in core/modules/views/src/Plugin/views/HandlerBase.php
ImageStyleEditForm.php in core/modules/image/src/Form/ImageStyleEditForm.php
InOperator.php in core/modules/views/src/Plugin/views/filter/InOperator.php
install.inc in core/includes/install.inc
API functions for installing modules and themes.
JsOptimizer.php in core/lib/Drupal/Core/Asset/JsOptimizer.php
LinkFieldTest.php in core/modules/link/tests/src/Functional/LinkFieldTest.php
LinkFormatter.php in core/modules/link/src/Plugin/Field/FieldFormatter/LinkFormatter.php
LinkSeparateFormatter.php in core/modules/link/src/Plugin/Field/FieldFormatter/LinkSeparateFormatter.php
MenuLink.php in core/modules/menu_link_content/src/Plugin/migrate/source/MenuLink.php
MenuLinkTest.php in core/modules/menu_link_content/tests/src/Kernel/Plugin/migrate/source/MenuLinkTest.php
MenuParentFormSelector.php in core/lib/Drupal/Core/Menu/MenuParentFormSelector.php
OverviewTerms.php in core/modules/taxonomy/src/Form/OverviewTerms.php
Page.php in core/modules/views/src/Plugin/views/display/Page.php
PathBasedBreadcrumbBuilder.php in core/modules/system/src/PathBasedBreadcrumbBuilder.php
PathPluginBase.php in core/modules/views/src/Plugin/views/display/PathPluginBase.php
PathProcessorLanguage.php in core/modules/language/src/HttpKernel/PathProcessorLanguage.php
RestExport.php in core/modules/rest/src/Plugin/views/display/RestExport.php
Schema.php in core/modules/mysql/src/Driver/Database/mysql/Schema.php
SchemaTest.php in core/modules/mysql/tests/src/Kernel/mysql/SchemaTest.php
search.module in core/modules/search/search.module
Enables site-wide keyword searching.
SearchPageTextTest.php in core/modules/search/tests/src/Functional/SearchPageTextTest.php
SearchPluginBase.php in core/modules/search/src/Plugin/SearchPluginBase.php
SearchTextProcessor.php in core/modules/search/src/SearchTextProcessor.php
system.install in core/modules/system/system.install
Install, update and uninstall functions for the system module.
text.module in core/modules/text/text.module
Defines simple text field types.
UnicodeTest.php in core/tests/Drupal/Tests/Component/Utility/UnicodeTest.php
user.module in core/modules/user/user.module
Enables the user registration and login system.
ViewFormBase.php in core/modules/views_ui/src/ViewFormBase.php
views_ui.module in core/modules/views_ui/views_ui.module
Provide structure for the administrative interface to Views.
VocabularyPermissionsTest.php in core/modules/taxonomy/tests/src/Functional/VocabularyPermissionsTest.php
WizardTest.php in core/modules/views_ui/tests/src/Functional/WizardTest.php

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