bug #21064 [Debug] Wrap call to ->log in a try catch block (lyrixx)

This PR was merged into the 2.7 branch.

Discussion
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[Debug] Wrap call to ->log in a try catch block

| Q             | A
| ------------- | ---
| Branch?       | 2.7
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets |
| License       | MIT
| Doc PR        |

---

If something goes wrong in the logger, the application ends up with a blank page. Let's display the original exception.

Commits
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18dfef1 [Debug] Wrap call to ->log in a try catch block

src/Symfony/Component/Debug/ErrorHandler.php

@@ -504,7 +504,11 @@ public function handleException($exception, array $error = null)
             }
         }
         if ($this->loggedErrors & $type) {
-            $this->loggers[$type][0]->log($this->loggers[$type][1], $message, $e);
+            try {
+                $this->loggers[$type][0]->log($this->loggers[$type][1], $message, $e);
+            } catch (\Exception $handlerException) {
+            } catch (\Throwable $handlerException) {
+            }
         }
         if ($exception instanceof FatalErrorException && !$exception instanceof OutOfMemoryException && $error) {
             foreach ($this->getFatalErrorHandlers() as $handler) {