Fix EZP-23283: Japanese URL are not matched

Link: https://jira.ez.no/browse/EZP-23283

## Description
When calling an URL of a content with a Japanese name like:
``` http://ez5.local/eng/私は日本の名前で試してみる必要が ```

The URI is encoded and looks like:
```http://ez5.local/eng/%E7%A7%81%E3%81%AF%E6%97%A5%E6%9C%AC%E3%81%AE%E5%90%8D%E5%89%8D%E3%81%A7%E8%A9%A6%E3%81%97%E3%81%A6%E3%81%BF%E3%82%8B%E5%BF%85%E8%A6%81%E3%81%8C ```

So once it is hashed to be looked up in:
https://github.com/ezsystems/ezpublish-kernel/blob/master/eZ/Publish/Core/Persistence/Legacy/Content/UrlAlias/Handler.php#L489
it can not be found.

## Tests
Manual tests

but this should be documented on why it needs the decoding, and why not with urldecode(). Because $request most likely takes it data from PHP superglobals which are already decoded: http://fr2.php.net/manual/en/function.urldecode.php#refsect1-function.urldecode-notes