feature #43148 [Cache] Throw ValueError in debug mode when serialization fails (nicolas-grekas)

This PR was merged into the 5.4 branch.

Discussion
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[Cache] Throw ValueError in debug mode when serialization fails

| Q             | A
| ------------- | ---
| Branch?       | 5.4
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | -
| Tickets       | Fix #41685
| License       | MIT
| Doc PR        | -

This feature allows spotting mistakes at the dev stage when trying to store unserializable objects (typically a closure) into a cache.

This PR replaces #42241 with a simpler and more focused approach: here we fail via a simple `ValueError`, which won't get caught by any try/catch into the Cache component, and we fail only when serialization fails - not on any failures of cache pool methods.

Commits
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0d3ede7725 [Cache] Throw ValueError in debug mode when serialization fails

Author: nicolas-grekas

Resources/config/cache.php

@@ -217,6 +217,7 @@
         ->set('cache.default_marshaller', DefaultMarshaller::class)
             ->args([
                 null, // use igbinary_serialize() when available
+                '%kernel.debug%',
             ])
 
         ->set('cache.early_expiration_handler', EarlyExpirationHandler::class)