1. Symfony 3.x removes yml class parameters, so:

• for cases we override them we need to use compiler pass instead
• for cases where we reuse them we need to set the actual class name like symfony itself does now
  2. Parameters needs to be in quotes
  3. Symfony 3 layout compatibility

First PR done on this: https://github.com/ezsystems/ezpublish-kernel/pull/1905
Second: https://github.com/ezsystems/ezpublish-kernel/pull/1910#discussion_r100760445