bug #38226 [FrameworkBundle] loadRoutes shoud receive RoutingPhpFileLoader (grachevko)

This PR was merged into the 5.1 branch.

Discussion
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[FrameworkBundle] loadRoutes shoud receive RoutingPhpFileLoader

| Q             | A
| ------------- | ---
| Branch?       | 5.1
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| License       | MIT
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In case when `sensio_framework_extra.router.annotations` options is set to `true` or not defined will throw this error

> In RoutingConfigurator.php line 28:
>
>  Argument 2 passed to Symfony\Component\Routing\Loader\Configurator\RoutingConfigurator::__construct() must be an instance of Symfony\Component\Routing\Loader\PhpFileLoader, instance of Symfony\Component\Routing\Loader\AnnotationFileLoader given, called in /opt/app/vendor/symfony/framework-bundle/Kernel/MicroKernelTrait.php on line 176

Commits
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25a1131e47 loadRoutes shoud receive RoutingPhpFileLoader

src/Symfony/Bundle/FrameworkBundle/Kernel/MicroKernelTrait.php

@@ -152,7 +152,7 @@ trait MicroKernelTrait
     {
         $file = (new \ReflectionObject($this))->getFileName();
         /* @var RoutingPhpFileLoader $kernelLoader */
-        $kernelLoader = $loader->getResolver()->resolve($file);
+        $kernelLoader = $loader->getResolver()->resolve($file, 'php');
         $kernelLoader->setCurrentDir(\dirname($file));
         $collection = new RouteCollection();