minor #16186 [2.7][tests] Use @requires annotation when possible (nicolas-grekas)

This PR was merged into the 2.7 branch.

Discussion
----------

[2.7][tests] Use @requires annotation when possible

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

Commits
-------

b028aea [tests] Use @requires annotation when possible

Author: nicolas-grekas

Tests/Console/Descriptor/JsonDescriptorTest.php

@@ -13,15 +13,11 @@
 
 use Symfony\Bundle\FrameworkBundle\Console\Descriptor\JsonDescriptor;
 
+/**
+ * @requires PHP 5.4
+ */
 class JsonDescriptorTest extends AbstractDescriptorTest
 {
-    protected function setUp()
-    {
-        if (PHP_VERSION_ID < 50400) {
-            $this->markTestSkipped('Test skipped on PHP 5.3 as JSON_PRETTY_PRINT does not exist.');
-        }
-    }
-
     protected function getDescriptor()
     {
         return new JsonDescriptor();

Tests/DependencyInjection/FrameworkExtensionTest.php

@@ -291,13 +291,10 @@ public function testValidation()
 
     /**
      * @group legacy
+     * @requires extension apc
      */
     public function testLegacyFullyConfiguredValidationService()
     {
-        if (!extension_loaded('apc')) {
-            $this->markTestSkipped('The apc extension is not available.');
-        }
-
         $container = $this->createContainerFromFile('full');
 
         $this->assertInstanceOf('Symfony\Component\Validator\Validator\ValidatorInterface', $container->get('validator'));