minor #18296 [3.1] fix testing deprecation messages (xabbuh)

This PR was merged into the 3.1-dev branch.

Discussion
----------

[3.1] fix testing deprecation messages

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

* always restore the previous error handler
* throw `LogicExcetion` when unexpected error type is triggered

Commits
-------

0df544f fix testing deprecation messages

Author: fabpot

Tests/Templating/TemplateNameParserTest.php

@@ -91,7 +91,9 @@ public function testAbsolutePathsAreDeprecated($name, $logicalName, $path, $ref)
         $deprecations = array();
         set_error_handler(function ($type, $msg) use (&$deprecations) {
             if (E_USER_DEPRECATED !== $type) {
-                throw new \LogicException(sprintf('Unexpected error: "%s".', $msg));
+                restore_error_handler();
+
+                return call_user_func_array('PHPUnit_Util_ErrorHandler::handleError', func_get_args());
             }
 
             $deprecations[] = $msg;