Issue #2112237 by vijaycs85, neclimdul, damiankloip: Fixed Regression: Remove EntityFormControllerNG from book module.
Issue #1851414 by nod_, quicksketch, frega, dawehner, damiankloip: Convert Views to use the abstracted dialog modal.
Issue #2043527 followup by tim.plunkett: Fixed Theme name is included in block machine name but should be stored as a key instead.
Issue #1914070 by Sutharsan, pp, YesCT: Improve version fallback for install language.
Revert "Issue #1914070 by Sutharsan, pp, YesCT: Improve version fallback for install language."

This reverts commit 7b08fd63984de56429a3b8620e92579e10debd20.
Issue #1914070 by Sutharsan, pp, YesCT: Improve version fallback for install language.
Issue #2036689 by batigolix, babruix, linclark: Create hook_help() for Serialization module.
Issue #2113547 by olli: Fixed Running ViewsDataHelperTest with phpunit fails.
Merge remote-tracking branch 'origin/8.x' into rest-url-patterns-2019123