minor #27109 [Form] fixes instance variable phpdoc in FormRegistry cl…

…ass (hhamon)

This PR was merged into the 2.7 branch.

Discussion
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[Form] fixes instance variable phpdoc in FormRegistry class

| Q             | A
| ------------- | ---
| Branch?       | 2.7
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | ~
| License       | MIT
| Doc PR        | ~

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Commits
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27fddf5 [Form] fixes instance variable phpdoc in FormRegistry class

src/Symfony/Component/Form/FormRegistry.php

@@ -30,7 +30,7 @@ class FormRegistry implements FormRegistryInterface
     private $extensions = array();
 
     /**
-     * @var FormTypeInterface[]
+     * @var ResolvedFormTypeInterface[]
      */
     private $types = array();