bug symfony#23082 [MonologBridge] Do not silence errors in ServerLogHandler::formatRecord (lyrixx)

This PR was merged into the 3.3 branch.

Discussion
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[MonologBridge] Do not silence errors in ServerLogHandler::formatRecord

| Q             | A
| ------------- | ---
| Branch?       | 3.3
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

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Commits
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f1edfa7 [MonologBridge] Do not silence errors in ServerLogHandler::formatRecord

Author: fabpot

src/Symfony/Bridge/Monolog/Handler/ServerLogHandler.php

@@ -51,9 +51,15 @@ public function handle(array $record)
             if (!$this->socket = $this->socket ?: $this->createSocket()) {
                 return false === $this->bubble;
             }
+        } finally {
+            restore_error_handler();
+        }
 
-            $recordFormatted = $this->formatRecord($record);
+        $recordFormatted = $this->formatRecord($record);
 
+        set_error_handler(self::class.'::nullErrorHandler');
+
+        try {
             if (-1 === stream_socket_sendto($this->socket, $recordFormatted)) {
                 stream_socket_shutdown($this->socket, STREAM_SHUT_RDWR);