[FrameworkBundle] added support for double-quoted strings in the extractor (closes #8797)
merged branch fabpot/extrator-fix (PR #8869)

This PR was merged into the 2.2 branch.

Discussion
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[FrameworkBundle] added support for double-quoted strings in the extractor (closes #8797)

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #8797
| License       | MIT
| Doc PR        | n/a

Commits
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4922a80 [FrameworkBundle] added support for double-quoted strings in the extractor (closes #8797)