Revert "Issue #1314214 by stefan.r, phayes, ergophobe, YesCT, damienwhaley, Tor Arne Thune, kbasarab, pfrenssen, basic, yannickoo, simolokid: MySQL driver does not support full UTF-8 (emojis, asian symbols, mathematical symbols)"

This reverts commit b105158a.

Issue #1314214 by stefan.r, phayes, ergophobe, YesCT, damienwhaley, Tor Arne Thune, kbasarab, pfrenssen, basic, yannickoo, simolokid: MySQL driver does not support full UTF-8 (emojis, asian symbols, mathematical symbols)

Issue #2428795 by mkalkbrenner, plach, yched, catch, hchonov, webchick, tstoeckler, pjonckiere, miro_dietiker, Schnitzel, klausi: Translatable entity 'changed' timestamps are not working at all

Issue #1923406 by stefan.r, yannickoo, catch, Crell, amateescu, pwolanin, morgantocker, Damien Tournoud, sun: Use ASCII character set on alphanumeric fields so we can index all 255 characters

Revert "Issue #1923406 by stefan.r, yannickoo: Use ASCII character set on alphanumeric fields so we can index all 255 characters"

This reverts commit ac4e35ce.

Issue #1923406 by stefan.r, yannickoo: Use ASCII character set on alphanumeric fields so we can index all 255 characters

Revert "Issue #2388749 by alexpott, adci_contributor, ParisLiakos: Register symfony's mime guessers if they are supported"

This reverts commit 4dae1d99.

Issue #2388749 by alexpott, adci_contributor, ParisLiakos: Register symfony's mime guessers if they are supported

Issue #2232477 by plach, yched, tstoeckler, amateescu: Fatal when adding new fields with NOT NULL constraints in a base table that contains existing entities

Issue #2143729 by tstoeckler, plach, jsbalsera, Berdir, mauzeh, damiankloip, andypost: Entity definitions miss a language entity key

Issue #2068655 by Berdir, chx, martin107, longwave, webflo, damiankloip, lokapujya, JacobSanford: Entity fields do not support case sensitive queries

Issue #2326949 by plach, effulgentsia: Move entity-type-specific schema information from the storage class to a schema handler.

Issue #1976158 by Berdir | msonnabaum: Rename entity storage/list/form/render "controllers" to handlers.

Issue #2319671 by dawehner, jhodgdon, xjm, alexpott: ViewsDataController: Step1: Move entity views data into controllers.

Issue #2154435 by andypost, Berdir, mparker17: Rename EntityAccessController to EntityAccessControlHandler.

Issue #2078473 by blueminds | Berdir: Added Use entity access API for checking access to private files.

Issue #2246665 by jaredsmith, martin107, YesCT, filijonka, tstoeckler: Typehint with Drupal\Core\Language\LanguageInterface instead Drupal\Core\Language\Language.

Issue #2183231 by tstoeckler, plach, jessebeach, fago, Berdir, xjm, mauzeh: Make ContentEntityDatabaseStorage generate static database schemas for content entities.

Issue #2145103 by Berdir, das-peter, fago, amateescu: Provide non-configurable field types for entity created, changed and timestamp fields.

Issue #2114707 by Berdir, yched, amateescu, effulgentsia, fago: Allow per-bundle overrides of field definitions.

Issue #2119905 by damiankloip, tim.plunkett, Berdir: Provide @ConfigEntityType and @ContentEntityType to have better defaults.

Issue #2078387 by Xano, andypost, twistor, splatio, InternetDevels, amateescu, Berdir, larowlan, vladan.me: Add an EntityOwnerInterface.

Issue #2074475 by benjy, Gábor Hojtsy: Rename {file_managed}.timestamp to 'changed' and add a created timestamp.

Temporary rollback since it conflicts with a critical issue.

This reverts commit ce08ea73.