10 files declare their use of Breakpoint

breakpoint.module in drupal/core/modules/breakpoint/breakpoint.module
Manage breakpoints and breakpoint groups for responsive designs.
BreakpointAPITest.php in drupal/core/modules/breakpoint/lib/Drupal/breakpoint/Tests/BreakpointAPITest.php
Definition of Drupal\breakpoint\Tests\BreakpointAPITest.
BreakpointCRUDTest.php in drupal/core/modules/breakpoint/lib/Drupal/breakpoint/Tests/BreakpointCRUDTest.php
Definition of Drupal\breakpoint\Tests\BreakpointCRUDTest.
BreakpointGroupAPITest.php in drupal/core/modules/breakpoint/lib/Drupal/breakpoint/Tests/BreakpointGroupAPITest.php
Definition of Drupal\breakpoint\Tests\BreakpointGroupAPITest.
BreakpointGroupCRUDTest.php in drupal/core/modules/breakpoint/lib/Drupal/breakpoint/Tests/BreakpointGroupCRUDTest.php
Definition of Drupal\breakpoint\Tests\BreakpointGroupCRUDTest.
BreakpointMediaQueryTest.php in drupal/core/modules/breakpoint/tests/Drupal/breakpoint/Tests/BreakpointMediaQueryTest.php
Definition of Drupal\breakpoint\Tests\BreakpointMediaQueryTest.
BreakpointTestBase.php in drupal/core/modules/breakpoint/lib/Drupal/breakpoint/Tests/BreakpointTestBase.php
Definition of Drupal\breakpoint\Tests\BreakpointTestBase.
BreakpointThemeTest.php in drupal/core/modules/breakpoint/lib/Drupal/breakpoint/Tests/BreakpointThemeTest.php
Definition of Drupal\breakpoint\Tests\BreakpointsThemeTest.
PictureAdminUITest.php in drupal/core/modules/picture/lib/Drupal/picture/Tests/PictureAdminUITest.php
Definition of Drupal\picture\Tests\PictureAdminUITest.
PictureFieldDisplayTest.php in drupal/core/modules/picture/lib/Drupal/picture/Tests/PictureFieldDisplayTest.php
Definition of Drupal\picture\Tests\PictureFieldDisplayTest.