[TwigBundle] Added missing files for phpunit
merged branch hason/twig_bundle (PR #8062)

This PR was merged into the 2.3 branch.

Discussion
----------

[TwigBundle] Added missing files for phpunit

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

Commits
-------

2952269 [TwigBundle] Added missing files for phpunit