minor #9742 ErrorHandlerTest: restore_error_handler() on assertion failure (nicolas-grekas)

This PR was submitted for the 2.4-dev branch but it was merged into the 2.4 branch instead (closes #9742).

Discussion
----------

ErrorHandlerTest: restore_error_handler() on assertion failure

Before the patch, if any test fail in src/Symfony/Component/Debug/Tests/ErrorHandlerTest.php,
phpunit's error handler is not correctly restored.
When running a test batch, this breaks other tests that rely on its behavior (@expectedException PHPUnit_Framework_Error)

Commits
-------

a6ed37c ErrorHandlerTest: restore_error_handler() on assertion failure

src/Symfony/Component/Debug/Tests/ErrorHandlerTest.php

@@ -90,6 +90,11 @@ PHP
             );
         } catch (DummyException $e) {
             // if an exception is thrown, the test passed
+        } catch (\Exception $e) {
+            restore_error_handler();
+            restore_exception_handler();
+
+            throw $e;
         }
 
         restore_error_handler();
@@ -135,6 +140,10 @@ PHP
             self::triggerNotice($this);
         } catch (DummyException $e) {
             // if an exception is thrown, the test passed
+        } catch (\Exception $e) {
+            restore_error_handler();
+
+            throw $e;
         }
 
         restore_error_handler();
@@ -150,6 +159,7 @@ PHP
 
     public function testConstruct()
     {
+        try {
             $handler = ErrorHandler::register(3);
 
             $level = new \ReflectionProperty($handler, 'level');
@@ -158,10 +168,16 @@ PHP
             $this->assertEquals(3, $level->getValue($handler));
 
             restore_error_handler();
+        } catch (\Exception $e) {
+            restore_error_handler();
+
+            throw $e;
+        }
     }
 
     public function testHandle()
     {
+        try {
             $handler = ErrorHandler::register(0);
             $this->assertFalse($handler->handle(0, 'foo', 'foo.php', 12, 'foo'));
 
@@ -216,6 +232,11 @@ PHP
             $handler->handle(E_USER_DEPRECATED, 'foo', 'foo.php', 12, 'foo');
 
             restore_error_handler();
+        } catch (\Exception $e) {
+            restore_error_handler();
+
+            throw $e;
+        }
     }
 
     /**