[META] Modernize Locale module

Locale module still has a bunch of legacy include files. As part of the core-wide initiative #3097045: [META] Provide modern replacements for and deprecate the legacy include files before Drupal 10 this issue focuses on Locale module.

Include files

• locale.batch.inc
  • 7 functions
• locale.bulk.inc
  • 14 functions
• locale.compare.inc
  • #3037031: Convert locale.compare.inc to a service (note 1)
• locale.fetch.inc
  • 3 functions
• locale.pages.inc
  • 2 functions
• locale.translation.inc
  • #3036982: Deprecate locale_translation_get_projects() and locale_translation_clear_cache_projects() (note 1)
  • 9 more functions

Module file

• #3037156: Locale import history service. Deprecate locale_translation_get_file_history(), locale_translation_update_file_history(), locale_translation_file_history_delete() (note 1)
• Approx 25 more functions

Constants

• #2831617: Deprecate global constants in locale module

Locale related, but not in scope

• #1834298: Unify name space in Locale module (note 2)
• #2935189: Complete docblock comments in Gettext component. (note 3)
• #1861360: Refactor localization update test so people can just enable the test module to test
• #2965866: Refactor LocaleUpdateBase to allow locale kernel tests
• #2927222: Move cache invalidation to event out of TranslateEditForm::submitForm()
• #2875279: Update core modules to use the new batch builder

Note 1: Part of #1577902: [META] Remove all usages of drupal_static() & drupal_static_reset()
Note 2: Part of #2999721: [META] Deprecate the legacy include files before Drupal 9
Note 3: Part of #1861442: [meta] Review of Drupal\Component\GetText files