Allow to autowire the default logger

[dunglas]

Q	A
Bug fix?	no
New feature?	yes
BC breaks?	no
Deprecations?	no
Tests pass?	yes
Fixed tickets	n/a
License	MIT
Doc PR	n/a

Related to symfony/symfony#16464. cc @weaverryan

[weaverryan]

👍

The idea is that when a bundle introduces multiple services with the same interface/class, that service cannot be auto-wired as a dependency into user-land services, as the container doesn't know which service to auto-wire. By adding this, the main logger will be auto-wired, which is really what you want. The user can still overwrite this in their code by creating a new service with this interface and setting its auto-write type.

@dunglas I assume that the monolog.logger tag would still change the auto-wired @logger service? http://symfony.com/doc/current/reference/dic_tags.html#monolog-logger

[dunglas]

Yes I've tried it it works.

[Seldaek]

Thanks!