bug #20760 [FrameworkBundle] [Workflow] Fix service marking store configuration (fduch)

This PR was submitted for the master branch but it was merged into the 3.2 branch instead (closes #20760).

Discussion
----------

[FrameworkBundle] [Workflow] Fix service marking store configuration

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

Currently workflow marking store configuration [checks](https://github.com/symfony/symfony/blob/3.2/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Configuration.php#L271-L272) that `service` and `arguments` fields are not specified simultaneously using `isset` function.

Since [arguments node](https://github.com/symfony/symfony/blob/3.2/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Configuration.php#L253-L261) defines prototype node inside, even if `arguments` node is not specified, -  after processing it looks like empty array. If `service` setting is set it leads to failing build with validation error message (due to `isset([])` returns `true`):
`"arguments" and "service" cannot be used together.`.

This patch addresses this issue.

Commits
-------

3289b10 [FrameworkBundle] [Workflow] Fix service marking store configuration

src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Configuration.php

@@ -268,7 +268,7 @@ class Configuration implements ConfigurationInterface
                                     ->thenInvalid('"type" and "service" cannot be used together.')
                                 ->end()
                                 ->validate()
-                                    ->ifTrue(function ($v) { return isset($v['arguments']) && isset($v['service']); })
+                                    ->ifTrue(function ($v) { return !empty($v['arguments']) && isset($v['service']); })
                                     ->thenInvalid('"arguments" and "service" cannot be used together.')
                                 ->end()
                             ->end()

src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/Fixtures/php/workflows.php

@@ -88,5 +88,23 @@ $container->loadFromExtension('framework', array(
                 ),
             ),
         ),
+        'service_marking_store_workflow' => array(
+            'marking_store' => array(
+                'service' => 'workflow_service',
+            ),
+            'supports' => array(
+                FrameworkExtensionTest::class,
+            ),
+            'places' => array(
+                'first',
+                'last',
+            ),
+            'transitions' => array(
+                'go' => array(
+                    'from' => 'first',
+                    'to' => 'last',
+                ),
+            ),
+        ),
     ),
 ));

src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/Fixtures/xml/workflows.xml

@@ -79,5 +79,16 @@
                 <framework:to>review</framework:to>
             </framework:transition>
         </framework:workflow>
+
+        <framework:workflow name="service_marking_store_workflow">
+            <framework:marking-store service="workflow_service"/>
+            <framework:support>Symfony\Bundle\FrameworkBundle\Tests\DependencyInjection\FrameworkExtensionTest</framework:support>
+            <framework:place>first</framework:place>
+            <framework:place>last</framework:place>
+            <framework:transition name="go">
+                <framework:from>first</framework:from>
+                <framework:to>last</framework:to>
+            </framework:transition>
+        </framework:workflow>
     </framework:config>
 </container>

src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/Fixtures/yml/workflows.yml

@@ -63,3 +63,17 @@ framework:
                 reopen:
                     from: closed
                     to: review
+        service_marking_store_workflow:
+            marking_store:
+                service: workflow_service
+            supports:
+                - Symfony\Bundle\FrameworkBundle\Tests\DependencyInjection\FrameworkExtensionTest
+            places:
+                - first
+                - last
+            transitions:
+                go:
+                    from:
+                        - first
+                    to:
+                        - last

src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/FrameworkExtensionTest.php

@@ -165,6 +165,12 @@ abstract class FrameworkExtensionTest extends TestCase
         $this->assertSame(array('workflow.definition' => array(array('name' => 'pull_request', 'type' => 'state_machine', 'marking_store' => 'single_state'))), $stateMachineDefinition->getTags());
         $this->assertCount(9, $stateMachineDefinition->getArgument(1));
         $this->assertSame('start', $stateMachineDefinition->getArgument(2));
+
+        $serviceMarkingStoreWorkflowDefinition = $container->getDefinition('workflow.service_marking_store_workflow');
+        /** @var Reference $markingStoreRef */
+        $markingStoreRef = $serviceMarkingStoreWorkflowDefinition->getArgument(1);
+        $this->assertInstanceOf(Reference::class, $markingStoreRef);
+        $this->assertEquals('workflow_service', (string) $markingStoreRef);
     }
 
     /**