The DebugBundle allows greater integration of the VarDumper component in the Symfony full-stack framework.
fabpot feature #27476 [Config] deprecate tree builders without root nodes (x…
…abbuh)

This PR was merged into the 4.2-dev branch.

Discussion
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[Config] deprecate tree builders without root nodes

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | yes
| Tests pass?   | yes
| Fixed tickets |
| License       | MIT
| Doc PR        |

While reviewing #27472 I wondered if we really need support config trees without a root node. If we did not support it, users wouldn't create pseudo configuration classes when they were actually not needed.

Commits
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c2ce15301c deprecate tree builders without root nodes
Latest commit ff481d1 Jun 25, 2018