bug #44820 [Cache] Don't lock when doing nested computations (nicolas…

…-grekas)

This PR was merged into the 4.4 branch.

Discussion
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[Cache] Don't lock when doing nested computations

| Q             | A
| ------------- | ---
| Branch?       | 4.4
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Tickets       | Fix #41130
| License       | MIT
| Doc PR        | -

Commits
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be8cbd2 [Cache] Don't lock when doing nested computations

src/Symfony/Component/Cache/LockRegistry.php

@@ -88,7 +88,7 @@ public static function compute(callable $callback, ItemInterface $item, bool &$s
 
         $key = self::$files ? abs(crc32($item->getKey())) % \count(self::$files) : -1;
 
-        if ($key < 0 || (self::$lockedFiles[$key] ?? false) || !$lock = self::open($key)) {
+        if ($key < 0 || self::$lockedFiles || !$lock = self::open($key)) {
             return $callback($item, $save);
         }