minor symfony#24961 [Console] remove debug dependency that was dead code (Tobion)

This PR was merged into the 4.0-dev branch.

Discussion
----------

[Console] remove debug dependency that was dead code

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | symfony#24873
| License       | MIT
| Doc PR        |

Commits
-------

453e799 [Console] remove debug dependency that was dead code

Author: Tobion

src/Symfony/Component/Console/Application.php

@@ -39,7 +39,6 @@
 use Symfony\Component\Console\Event\ConsoleTerminateEvent;
 use Symfony\Component\Console\Exception\CommandNotFoundException;
 use Symfony\Component\Console\Exception\LogicException;
-use Symfony\Component\Debug\Exception\FatalThrowableError;
 use Symfony\Component\EventDispatcher\EventDispatcherInterface;
 
 /**
@@ -120,13 +119,8 @@ public function run(InputInterface $input = null, OutputInterface $output = null
         $this->configureIO($input, $output);
 
         try {
-            $e = null;
             $exitCode = $this->doRun($input, $output);
-        } catch (\Exception $e) {
         } catch (\Throwable $e) {
-        }
-
-        if (null !== $e) {
             if (!$this->catchExceptions || !$e instanceof \Exception) {
                 throw $e;
             }
@@ -201,11 +195,12 @@ public function doRun(InputInterface $input, OutputInterface $output)
             if (null !== $this->dispatcher) {
                 $event = new ConsoleErrorEvent($input, $output, $e);
                 $this->dispatcher->dispatch(ConsoleEvents::ERROR, $event);
-                $e = $event->getError();
 
                 if (0 === $event->getExitCode()) {
                     return 0;
                 }
+
+                $e = $event->getError();
             }
 
             throw $e;
@@ -849,7 +844,6 @@ protected function doRunCommand(Command $command, InputInterface $input, OutputI
         }
 
         $event = new ConsoleCommandEvent($command, $input, $output);
-        $e = null;
 
         try {
             $this->dispatcher->dispatch(ConsoleEvents::COMMAND, $event);
@@ -862,10 +856,9 @@ protected function doRunCommand(Command $command, InputInterface $input, OutputI
         } catch (\Throwable $e) {
             $event = new ConsoleErrorEvent($input, $output, $e, $command);
             $this->dispatcher->dispatch(ConsoleEvents::ERROR, $event);
-            $e = $event->getError();
 
             if (0 !== $exitCode = $event->getExitCode()) {
-                throw $e;
+                throw $event->getError();
             }
         } finally {
             $event = new ConsoleTerminateEvent($command, $input, $output, $exitCode);

src/Symfony/Component/Console/composer.json

@@ -17,8 +17,7 @@
     ],
     "require": {
         "php": "^7.1.3",
-        "symfony/polyfill-mbstring": "~1.0",
-        "symfony/debug": "~3.4|~4.0"
+        "symfony/polyfill-mbstring": "~1.0"
     },
     "require-dev": {
         "symfony/config": "~3.4|~4.0",