minor #13925 [translation][initialize cache] Remove dead code. (aitboudad)

This PR was merged into the 2.6 branch.

Discussion
----------

[translation][initialize cache] Remove dead code.

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

I see two issues here:
1- initialize function doesn't exist in Translator class.
2- initializeCacheCatalogue is only called when cache is not null

Commits
-------

bc066fb [translation][initialize cache] Remove dead code.

src/Symfony/Component/Translation/Translator.php

@@ -351,12 +351,6 @@ class Translator implements TranslatorInterface, TranslatorBagInterface
             return;
         }
 
-        if (null === $this->cacheDir) {
-            $this->initialize();
-
-            return $this->loadCatalogue($locale);
-        }
-
         $this->assertValidLocale($locale);
         $cache = new ConfigCache($this->cacheDir.'/catalogue.'.$locale.'.php', $this->debug);
         if (!$cache->isFresh()) {