With the introduction of symfony/event-dispatcher-contracts
in https://git.typo3.org/Packages/TYPO3.CMS.git/commit/e4a1ae8762ee99712
we forced usage of symfony5 in composer-based installations where
installation with symfony4 was possible before. This is because event
contracts v2 is only compatible with symfony v5, but contracts v1 needs to
be supported for symfony4 compatibility.

Note: although non-composer-based installations used symfony5 bundled
already, composer mode could still use symfony v4 if needed.

We now add a new intermediate composer package that is available in two
different versions, and offers a compatible symfony event dispatcher
adapter for the respective interfaces in symfony v4 and symfony v5 in each
of these version. typo3/cms-core allows to install both versions which
means we can provide a compatible adapter for both, symfony v4 and v5.

This change allows composer-based installations to support both
versions (v5/v4) again, so extensions like EXT:solr (which requires
a package called solarium) to work with the dependency constraints
of TYPO3 Core.

Commands used:

  composer require --no-update --working-dir=typo3/sysext/core \
    "symfony/event-dispatcher-contracts:^1.1 || ^2.0" \
    "typo3/symfony-psr-event-dispatcher-adapter:^1.0 || ^2.0"

  composer require --no-update \
    "symfony/event-dispatcher-contracts:^1.1 || ^2.0" \
    "typo3/symfony-psr-event-dispatcher-adapter:^1.0 || ^2.0"

  composer update --lock

Resolves: #92229
Releases: master, 10.4
Change-Id: I4ff6c6589833cbfea3c4b327a8580fd5fbf45468
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/65644


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Helmut Hummel <typo3@helhum.io>
Tested-by: Simon Gilli <typo3@gilbertsoft.org>
Tested-by: Benjamin Franzke <bfr@qbus.de>
Reviewed-by: Simon Gilli <typo3@gilbertsoft.org>
Reviewed-by: Helmut Hummel <typo3@helhum.io>
Reviewed-by: Benjamin Franzke <bfr@qbus.de>