minor #13274 [2.6] Added internal annotation on Descriptor classes (saro0h)

This PR was merged into the 2.6 branch.

Discussion
----------

[2.6] Added internal annotation on Descriptor classes

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

Commits
-------

6776ab3 [2.6] Added internal annotation on Descriptor classes

src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/Descriptor.php

@@ -24,6 +24,8 @@ use Symfony\Component\Routing\RouteCollection;
 
 /**
  * @author Jean-François Simon <jeanfrancois.simon@sensiolabs.com>
+ *
+ * @internal
  */
 abstract class Descriptor implements DescriptorInterface
 {

src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/JsonDescriptor.php

@@ -25,6 +25,8 @@ use Symfony\Component\Routing\RouteCollection;
 
 /**
  * @author Jean-François Simon <jeanfrancois.simon@sensiolabs.com>
+ *
+ * @internal
  */
 class JsonDescriptor extends Descriptor
 {

src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/MarkdownDescriptor.php

@@ -21,6 +21,8 @@ use Symfony\Component\Routing\RouteCollection;
 
 /**
  * @author Jean-François Simon <jeanfrancois.simon@sensiolabs.com>
+ *
+ * @internal
  */
 class MarkdownDescriptor extends Descriptor
 {

src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/TextDescriptor.php

@@ -22,6 +22,8 @@ use Symfony\Component\Routing\RouteCollection;
 
 /**
  * @author Jean-François Simon <jeanfrancois.simon@sensiolabs.com>
+ *
+ * @internal
  */
 class TextDescriptor extends Descriptor
 {

src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/XmlDescriptor.php

@@ -22,6 +22,8 @@ use Symfony\Component\Routing\RouteCollection;
 
 /**
  * @author Jean-François Simon <jeanfrancois.simon@sensiolabs.com>
+ *
+ * @internal
  */
 class XmlDescriptor extends Descriptor
 {

src/Symfony/Bundle/FrameworkBundle/Console/Helper/DescriptorHelper.php

@@ -19,6 +19,8 @@ use Symfony\Component\Console\Helper\DescriptorHelper as BaseDescriptorHelper;
 
 /**
  * @author Jean-François Simon <jeanfrancois.simon@sensiolabs.com>
+ *
+ * @internal
  */
 class DescriptorHelper extends BaseDescriptorHelper
 {

src/Symfony/Component/Console/Descriptor/ApplicationDescription.php

@@ -16,6 +16,8 @@ use Symfony\Component\Console\Command\Command;
 
 /**
  * @author Jean-François Simon <jeanfrancois.simon@sensiolabs.com>
+ *
+ * @internal
  */
 class ApplicationDescription
 {

src/Symfony/Component/Console/Descriptor/Descriptor.php

@@ -20,6 +20,8 @@ use Symfony\Component\Console\Output\OutputInterface;
 
 /**
  * @author Jean-François Simon <jeanfrancois.simon@sensiolabs.com>
+ *
+ * @internal
  */
 abstract class Descriptor implements DescriptorInterface
 {

src/Symfony/Component/Console/Descriptor/JsonDescriptor.php

@@ -21,6 +21,8 @@ use Symfony\Component\Console\Input\InputOption;
  * JSON descriptor.
  *
  * @author Jean-François Simon <contact@jfsimon.fr>
+ *
+ * @internal
  */
 class JsonDescriptor extends Descriptor
 {

src/Symfony/Component/Console/Descriptor/MarkdownDescriptor.php

@@ -21,6 +21,8 @@ use Symfony\Component\Console\Input\InputOption;
  * Markdown descriptor.
  *
  * @author Jean-François Simon <contact@jfsimon.fr>
+ *
+ * @internal
  */
 class MarkdownDescriptor extends Descriptor
 {

src/Symfony/Component/Console/Descriptor/TextDescriptor.php

@@ -21,6 +21,8 @@ use Symfony\Component\Console\Input\InputOption;
  * Text descriptor.
  *
  * @author Jean-François Simon <contact@jfsimon.fr>
+ *
+ * @internal
  */
 class TextDescriptor extends Descriptor
 {

src/Symfony/Component/Console/Descriptor/XmlDescriptor.php

@@ -21,6 +21,8 @@ use Symfony\Component\Console\Input\InputOption;
  * XML descriptor.
  *
  * @author Jean-François Simon <contact@jfsimon.fr>
+ *
+ * @internal
  */
 class XmlDescriptor extends Descriptor
 {