Issue #1479454 by Hugo Wetterberg, galooph, andypost, marcingy, heyrocker, larowlan, alexpott, tim.plunkett, fubhy, sun, dawehner: Convert user roles to configurables.
Issue #1893400 by swentel, dawehner: Fixed Autocomplete is busted.
Issue #1884762 by tim.plunkett, Gábor Hojtsy: Block forms should use #type => machine_name().
Issue #1891692 by katbailey: Fixed AliasManagerCacheDecorator won't work correctly with subrequests.
Issue #1893534 by msonnabaum: Fixed Typehint the container interface instead of the class.
Issue #1817656 by tstoeckler, tim.plunkett, dawehner, alexpott: Let user_autocomplete() also find the anonymous user.
Issue #1893400 follow-up by sun: Switch autocomplete widget to type hidden, input false for more optimal fix.
Issue #1893400 follow-up by sun: REALLY fix autocomplete this time. :P
Revert "Issue #1893400 follow-up by sun: REALLY fix autocomplete this time. :P"

Wrong commit credit.

This reverts commit 922b0916aa641ad0cf8d0b4f3733e788f2a9bacd.
Issue #1893400 follow-up by nod_: REALLY fix autocomplete this time. :P
Issue #1722882 follow-up by Berdir: Fixed CacheDecorator does not clear used cache tags.
Issue #1893740 by Gábor Hojtsy: Remove repeated 'Block' UI text from block editing, fix title.