feature #32475 [Process] Deprecate Process::inheritEnvironmentVariables() (ogizanagi)

This PR was merged into the 4.4 branch.

Discussion
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[Process] Deprecate Process::inheritEnvironmentVariables()

| Q             | A
| ------------- | ---
| Branch?       | 4.4 <!-- see below -->
| Bug fix?      | no
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| BC breaks?    | no     <!-- see https://symfony.com/bc -->
| Deprecations? | yes <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tests pass?   | yes    <!-- please add some, will be required by reviewers -->
| Fixed tickets | N/A   <!-- #-prefixed issue number(s), if any -->
| License       | MIT
| Doc PR        | N/A

IIUC, this method was kept as a BC layer from 3.4 to 4.0 to switch to the "inherit env vars" behavior, inciting developers to opt-in in 3.4. Since 4.0, env vars are always inherited, and this method doesn't allow to opt-out. So, time to remove it?

---

refs:

- symfony/symfony#21470
- symfony/symfony#22836

Commits
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af9bad31c6 [Process] Deprecate Process::inheritEnvironmentVariables()

Author: nicolas-grekas

WebServer.php

@@ -167,7 +167,11 @@ private function createServerProcess(WebServerConfig $config)
 
         if (\in_array('APP_ENV', explode(',', getenv('SYMFONY_DOTENV_VARS')))) {
             $process->setEnv(['APP_ENV' => false]);
-            $process->inheritEnvironmentVariables();
+
+            if (!method_exists(Process::class, 'fromShellCommandline')) {
+                // Symfony 3.4 does not inherit env vars by default:
+                $process->inheritEnvironmentVariables();
+            }
         }
 
         return $process;