[Debug] less intrusive work around for https://bugs.php.net/54275
bug #10799 [Debug] less intrusive work around for https://bugs.php.net/54275 (nicolas-grekas)

This PR was merged into the 2.5-dev branch.

Discussion
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[Debug] less intrusive work around for https://bugs.php.net/54275

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #10787, #10292
| License       | MIT
| Doc PR        | none

- This PR supersedes the behavior introduced in https://github.com/symfony/symfony/pull/10725 :
  Instead of building some complicated code to work around https://bugs.php.net/54275, the code is now as
  straightforward as possible, with a conditional fallback work around.
- The handling of fatal errors is also made more robust/fail-safe.
- Last but not least, ErrorsLoggerListener and FatalErrorExceptionsListener are now registered earlier and
  are now cleaning up their handler/logger once set to prevent setting again and again for sub-requests
  (+remove one refcount for these handler and logger).

Commits
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d7a186f [Debug] less intrusive work around for https://bugs.php.net/54275