minor symfony#9059 Missing CompilerPassInterface (grzonu)

This PR was merged into the 4.0 branch.

Discussion
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Missing CompilerPassInterface

There are missing implement CompilerPassInterface to this example work properly.

Commits
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7369002 Missing CompilerPassInterface

Author: javiereguiluz

bundles/override.rst

@@ -56,8 +56,9 @@ example, the implementing class for the ``original-service-id`` is changed to
     // ...
     + use App\Service\YourService;
     + use Symfony\Component\DependencyInjection\ContainerBuilder;
+    + use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
 
-    class Kernel extends BaseKernel
+    class Kernel extends BaseKernel implements CompilerPassInterface
     {
     +     public function process(ContainerBuilder $container)
     +     {