$default can be string
minor #10184 [Console] $default can be string (Jmoati)

This PR was submitted for the 2.3-dev branch but it was merged into the 2.3 branch instead (closes #10184).

Discussion
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[Console] $default can be string

Bug fix: no
Feature addition: no
Backwards compatibility break: no
Symfony2 tests pass: yes
License of the code: MIT

Commits
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39ab7f3 [Console] $default can be string