Empty select with attribute name="foo[]" bug fix

If you have a select with attribute name="foo[]", and you submit your form, http_build_query returns empty string as a result. In this case you get a form extra field validation error, because your field "foo" converts to
'' => bool(false)
bug #10808 [DomCrawler] Empty select with attribute name="foo[]" bug fix (darles)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #10808).

Discussion
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[DomCrawler] Empty select with attribute name="foo[]" bug fix

If you have a select with attribute name="foo[]", and you submit your form, http_build_query returns empty string as a result. In this case you get a form extra field validation error, because your field "foo" converts to
'' => bool(false)

Commits
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15f081d Empty select with attribute name="foo[]" bug fix
issue #10808 crawler test
phpunit src/Symfony/Component/DomCrawler/Tests/FormTest.php #11066 #10808 crawler test (defrag)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #11066).

Discussion
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#10808 crawler test

 Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets |#10808
| License       | MIT

Adds test for #10808

Commits
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876d6ca issue #10808 crawler test