Revert "Issue #2343677 by damiankloip, znerol, Fabianx: Fixed Stack middleware suffers from incomplete service construction."

This reverts commit c033857b110f9ed6d2f6dba84efaf959d25db951.
Issue #2343677 by damiankloip, znerol, Fabianx, pounard: Fixed Stack middleware suffers from incomplete service construction.

This reverts commit 39eb84fc38d550153d4dde068c84cbc12282a40c.
Issue #2329901 by lanchez, lauriii | davidhernandez: Move form classes from preprocess to templates.
Issue #2226207 by lauriii, mgbellaire, Cottser, m1r1k, Mark Carver, LinL, rachel_norfolk, rteijeiro, skwashd, davidhernandez, euphoric_mv: Make 'template' the default output option for hook_theme().
Issue #2350301 by mitrpaka: Replace extend of deprecated DrupalUnitTestBase with KernelTestBase in Contextual.
Issue #2028053 by vegantriathlete, franxo, InternetDevels, thamas, rootwork, LewisNyman: Add typographic styles, components, and utility classes.
Issue #2346369 by Wim Leers: Support special '#attached' variable for attaching assets in preprocess functions.
Issue #2318377 by dawehner, Wim Leers, damiankloip: Determine whether a view is cacheable and its required contexts, store this i/t config entity.