minor #24685 Make it easy for Drupal to use the PHPUnit bridge (alexpott)

This PR was squashed before being merged into the 3.3 branch (closes #24685).

Discussion
----------

Make it easy for Drupal to use the PHPUnit bridge

| Q             | A
| ------------- | ---
| Branch?       | 3.3 <!-- see comment below -->
| Bug fix?      | no
| New feature?  | no <!-- don't forget to update src/**/CHANGELOG.md files -->
| BC breaks?    | no
| Deprecations? | no <!-- don't forget to update UPGRADE-*.md files -->
| Tests pass?   | yes
| Fixed tickets | #... <!-- #-prefixed issue number(s), if any -->
| License       | MIT
| Doc PR        | symfony/symfony-docs#... <!--highly recommended for new features-->

<!--
- Bug fixes must be submitted against the lowest branch where they apply
  (lowest branches are regularly merged to upper ones so they get the fixes too).
- Features and deprecations must be submitted against the 3.4,
  legacy code removals go to the master branch.
- Please fill in this template according to the PR you're about to submit.
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Drupal doesn't use src/Symfony/Bridge/PhpUnit/bin/simple-phpunit but would like to use the deprecation collection features of src/Symfony/Bridge/PhpUnit. The checks in src/Symfony/Bridge/PhpUnit/bootstrap.php mean that this is difficult because they rely on simple-phpunit - but I'm not sure that that is necessary.

Commits
-------

1de6bf8 Make it easy for Drupal to use the PHPUnit bridge

src/Symfony/Bridge/PhpUnit/Tests/DeprecationErrorHandler/default.phpt

@@ -12,8 +12,12 @@ $vendor = __DIR__;
 while (!file_exists($vendor.'/vendor')) {
     $vendor = dirname($vendor);
 }
-define('PHPUNIT_COMPOSER_INSTALL', $vendor.'/vendor/autoload.php');
-require PHPUNIT_COMPOSER_INSTALL;
+// Fake class to ensure bootstrap.php calls DeprecationErrorHandler::register().
+class PHPUnit_TextUI_Command
+{
+
+}
+require  $vendor.'/vendor/autoload.php';
 require_once __DIR__.'/../../bootstrap.php';
 
 @trigger_error('root deprecation', E_USER_DEPRECATED);

src/Symfony/Bridge/PhpUnit/Tests/DeprecationErrorHandler/disabled.phpt

@@ -12,8 +12,12 @@ $vendor = __DIR__;
 while (!file_exists($vendor.'/vendor')) {
     $vendor = dirname($vendor);
 }
-define('PHPUNIT_COMPOSER_INSTALL', $vendor.'/vendor/autoload.php');
-require PHPUNIT_COMPOSER_INSTALL;
+// Fake class to ensure bootstrap.php calls DeprecationErrorHandler::register().
+class PHPUnit_TextUI_Command
+{
+
+}
+require  $vendor.'/vendor/autoload.php';
 require_once __DIR__.'/../../bootstrap.php';
 
 echo (int) set_error_handler('var_dump');

src/Symfony/Bridge/PhpUnit/Tests/DeprecationErrorHandler/regexp.phpt

@@ -12,8 +12,12 @@ $vendor = __DIR__;
 while (!file_exists($vendor.'/vendor')) {
     $vendor = dirname($vendor);
 }
-define('PHPUNIT_COMPOSER_INSTALL', $vendor.'/vendor/autoload.php');
-require PHPUNIT_COMPOSER_INSTALL;
+// Fake class to ensure bootstrap.php calls DeprecationErrorHandler::register().
+class PHPUnit_TextUI_Command
+{
+
+}
+require  $vendor.'/vendor/autoload.php';
 require_once __DIR__.'/../../bootstrap.php';
 
 @trigger_error('root deprecation', E_USER_DEPRECATED);

src/Symfony/Bridge/PhpUnit/Tests/DeprecationErrorHandler/weak.phpt

@@ -12,8 +12,12 @@ $vendor = __DIR__;
 while (!file_exists($vendor.'/vendor')) {
     $vendor = dirname($vendor);
 }
-define('PHPUNIT_COMPOSER_INSTALL', $vendor.'/vendor/autoload.php');
-require PHPUNIT_COMPOSER_INSTALL;
+// Fake class to ensure bootstrap.php calls DeprecationErrorHandler::register().
+class PHPUnit_TextUI_Command
+{
+
+}
+require  $vendor.'/vendor/autoload.php';
 require_once __DIR__.'/../../bootstrap.php';
 
 @trigger_error('root deprecation', E_USER_DEPRECATED);

src/Symfony/Bridge/PhpUnit/Tests/DeprecationErrorHandler/weak_vendors_on_non_vendor.phpt

@@ -12,8 +12,12 @@ $vendor = __DIR__;
 while (!file_exists($vendor.'/vendor')) {
     $vendor = dirname($vendor);
 }
-define('PHPUNIT_COMPOSER_INSTALL', $vendor.'/vendor/autoload.php');
-require PHPUNIT_COMPOSER_INSTALL;
+// Fake class to ensure bootstrap.php calls DeprecationErrorHandler::register().
+class PHPUnit_TextUI_Command
+{
+
+}
+require  $vendor.'/vendor/autoload.php';
 require_once __DIR__.'/../../bootstrap.php';
 
 @trigger_error('root deprecation', E_USER_DEPRECATED);

src/Symfony/Bridge/PhpUnit/Tests/DeprecationErrorHandler/weak_vendors_on_vendor.phpt

@@ -12,8 +12,12 @@ $vendor = __DIR__;
 while (!file_exists($vendor.'/vendor')) {
     $vendor = dirname($vendor);
 }
-define('PHPUNIT_COMPOSER_INSTALL', $vendor.'/vendor/autoload.php');
-require PHPUNIT_COMPOSER_INSTALL;
+// Fake class to ensure bootstrap.php calls DeprecationErrorHandler::register().
+class PHPUnit_TextUI_Command
+{
+
+}
+require  $vendor.'/vendor/autoload.php';
 require_once __DIR__.'/../../bootstrap.php';
 require __DIR__.'/fake_vendor/autoload.php';
 require __DIR__.'/fake_vendor/acme/lib/deprecation_riddled.php';

src/Symfony/Bridge/PhpUnit/bootstrap.php

@@ -13,7 +13,7 @@ use Doctrine\Common\Annotations\AnnotationRegistry;
 use Symfony\Bridge\PhpUnit\DeprecationErrorHandler;
 
 // Detect if we're loaded by an actual run of phpunit
-if (!defined('PHPUNIT_COMPOSER_INSTALL') && !class_exists('PHPUnit_TextUI_Command', false) && !class_exists('PHPUnit\TextUI\Command', false)) {
+if (!class_exists('PHPUnit_TextUI_Command', false) && !class_exists('PHPUnit\TextUI\Command', false)) {
     if ($ser = getenv('SYMFONY_DEPRECATIONS_SERIALIZE')) {
         DeprecationErrorHandler::collectDeprecations($ser);
     }