Issue #3087517 by mdupont, longwave, kim.pepper: Remove BC layer for Pager service

core/globals.api.php

core/includes/pager.inc

core/includes/theme.inc

core/lib/Drupal/Core/Cache/Context/PagersCacheContext.php

core/lib/Drupal/Core/DrupalKernel.php

core/lib/Drupal/Core/Pager/PagerManager.php

core/lib/Drupal/Core/Pager/PagerManagerInterface.php

...es/system/tests/src/Kernel/Pager/PagerDeprecationTest.php

...dules/system/tests/src/Unit/Pager/PreprocessPagerTest.php

core/modules/views/src/Plugin/views/pager/SqlBase.php

core/modules/views/src/Plugin/views/query/Sql.php

core/modules/views/views.module

.../tests/Drupal/KernelTests/Core/Pager/PagerManagerTest.php