minor symfony#19268 [Validator] add missing interface use statement for phpdoc block return type (hhamon)

This PR was merged into the 3.0 branch.

Discussion
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[Validator] add missing interface use statement for phpdoc block return type

| 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        | ~

Commits
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43dff0e [Validator] add missing interface use statement for phpdoc block return type.

Author: fabpot

src/Symfony/Component/Validator/Mapping/Factory/MetadataFactoryInterface.php

@@ -11,7 +11,8 @@
 
 namespace Symfony\Component\Validator\Mapping\Factory;
 
-use Symfony\Component\Validator\Exception;
+use Symfony\Component\Validator\Exception\NoSuchMetadataException;
+use Symfony\Component\Validator\Mapping\MetadataInterface;
 
 /**
  * Returns {@link \Symfony\Component\Validator\Mapping\MetadataInterface} instances for values.
@@ -29,7 +30,7 @@ interface MetadataFactoryInterface
      *
      * @return MetadataInterface The metadata for the value
      *
-     * @throws Exception\NoSuchMetadataException If no metadata exists for the given value
+     * @throws NoSuchMetadataException If no metadata exists for the given value
      */
     public function getMetadataFor($value);