Move all functions from content_translation.pages.inc file to Drupal\content_translation\Controller\ContentTranslationController class

move content_translation_overview() body to ContentTranslationController::overview()
remove content_translation_overview()

There are already tests created for this at:
Drupal\content_translation\Tests\ContentTranslationUITest

Could not remove: module_load_include('pages.inc', 'content_translation');
because there are other functions from content_translation.pages.inc file that are called in the controller.

I decided to move all functions from content_translation.pages.inc to the Drupal\content_translation\Controller\ContentTranslationController class.
Functions from content_translation.pages.inc are only used in the ContentTranslationController.
Furthermore, I will delete file content_translation.pages.inc.
I will remove @todo from comments for ContentTranslationController

Solve all tasks specified in motivation.

Thank you for the patch. Here are some minor issues.

1. +++ b/core/modules/content_translation/lib/Drupal/content_translation/Controller/ContentTranslationController.php
   @@ -15,33 +18,222 @@
   +    drupal_set_message($entity->getSystemPath('drupal:content-translation-overview'));
   

   I think this is for debugging. So we can remove it. You can use debug() function in D8 instead of dsm();

2. +++ b/core/modules/content_translation/lib/Drupal/content_translation/Controller/ContentTranslationController.php
   @@ -15,33 +18,222 @@
   +    $administrator = \Drupal::currentUser()->hasPermission('administer languages');
   ...
   +    if (\Drupal::languageManager()->isMultilingual()) {
   ...
   +    $target = !empty($target) ? $target : \Drupal::languageManager()->getCurrentLanguage(Language::TYPE_CONTENT);
   ...
   +    return \Drupal::service('entity.form_builder')->getForm($entity, 'default', $form_state);
   ...
   +    $language = !empty($language) ? $language : \Drupal::languageManager()->getCurrentLanguage(Language::TYPE_CONTENT);
   ...
   +    return \Drupal::service('entity.form_builder')->getForm($entity, 'default', $form_state);
   ...
   +    $links = \Drupal::languageManager()->getLanguageSwitchLinks(Language::TYPE_CONTENT, $path);
   ...
   +    $links = \Drupal::languageManager()->getLanguageSwitchLinks(Language::TYPE_INTERFACE, $path);
   

   We can remove \Drupal usage in Controller and use constructor injections.

3. +++ b/core/modules/content_translation/lib/Drupal/content_translation/Controller/ContentTranslationController.php
   @@ -15,33 +18,222 @@
   +          // If the user is allowed to edit the entity we point the edit link to
   

   more then 80 chars.

4. +++ b/core/modules/content_translation/lib/Drupal/content_translation/Controller/ContentTranslationController.php
   @@ -15,33 +18,222 @@
   +  ¶
   ...
   +    return $links; ¶
   ...
   +  ¶
   ...
   +  ¶
   

   Whitespace.

Small improvements as specified in comment #16.

Please post the interdiff.

1. +++ b/core/modules/content_translation/lib/Drupal/content_translation/Controller/ContentTranslationController.php
   @@ -8,40 +8,232 @@
   +    $header = array(t('Language'), t('Translation'), t('Source language'), t('Status'), t('Operations'));
   

   We can use $this->t instead of t.

2. +++ b/core/modules/content_translation/lib/Drupal/content_translation/Controller/ContentTranslationController.php
   @@ -8,40 +8,232 @@
   +          // If the user is allowed to edit the entity we point the edit link to
   

   more then 80 chars.

Solved issues from comment #19.
Provide interdiff.
Waiting for feedback.

Wow! This looks really awesome. Thanks for working on this, Andrei. Some small nitpicks:

1. +++ b/core/modules/content_translation/lib/Drupal/content_translation/Controller/ContentTranslationController.php
   @@ -8,40 +8,233 @@
   +use \Drupal\Core\Controller\ControllerBase;
   

   Remove the trailing backslash.

2. +++ b/core/modules/content_translation/lib/Drupal/content_translation/Controller/ContentTranslationController.php
   @@ -8,40 +8,233 @@
   +   * @param EntityInterface $entity
   +   *   The entity being translated.
   ...
      public function add(Request $request, $source, $target) {
   

   The phpdoc first argument says that this is an entity, but it is not.

   Add typehinting: add(Request $request, Language $source, Language $target). This way IDEs can help autocompleting.

3. +++ b/core/modules/content_translation/lib/Drupal/content_translation/Controller/ContentTranslationController.php
   @@ -8,40 +8,233 @@
   +   * @param Language $source
   ...
   +   * @param Language $target
   

   We should use here fully-qualified namespaces, as the other methods' phpdoc. See https://drupal.org/coding-standards/docs#types

4. +++ b/core/modules/content_translation/lib/Drupal/content_translation/Controller/ContentTranslationController.php
   @@ -8,40 +8,233 @@
   +    $links = $this->languageManager()->getLanguageSwitchLinks(Language::TYPE_INTERFACE, $path);
   

   Wrong indentation.

5. +++ b/core/modules/content_translation/lib/Drupal/content_translation/Controller/ContentTranslationController.php
   @@ -8,40 +8,233 @@
   +   *   The entitiy being translated.
   

   Typo: entitiy => entity.

Thank you penyaskito for you review.
I've fixed documentation.
Providin interdiff.
Waiting for you review again please.

Great progress, thank you very much andrei. Overall the patch looks great, some minor issues:

1. +++ b/core/modules/content_translation/lib/Drupal/content_translation/Controller/ContentTranslationController.php
   @@ -8,40 +8,236 @@
   +   * @param \Symfony\Component\HttpFoundation\Request $request
   +   *   The request obkect.
   

   object is misspelled in several places.

2. +++ b/core/modules/content_translation/lib/Drupal/content_translation/Controller/ContentTranslationController.php
   @@ -8,40 +8,236 @@
       */
   -  public function add(Request $request, $source, $target) {
   +  public function add(Request $request,$source,$target) {
        $entity = $request->attributes->get($request->attributes->get('_entity_type_id'));
   

   A comma should be followed by a space in the argument list (also several places).

3. +++ b/core/modules/content_translation/lib/Drupal/content_translation/Controller/ContentTranslationController.php
   @@ -8,40 +8,236 @@
   +   * @param \Drupal\Core\Language\Language $source
   +   *   The language to be used as source.
   +   * @param \Drupal\Core\Language\Language $target
   +   *   The language to be used as target.
   +   */
   +  public function prepareTranslation(EntityInterface $entity, Language $source, Language $target) {
   +    if ($entity instanceof ContentEntityInterface) {
   

   When type hinting, use an interface when possible. I.e. LanguageInterface instead of Language. A notable exception to this rule is the Request class, there is no interface for it.

Solved issues from the previous comment.
Providing interdiff.

This looks okay now. Let's get it in and move on. Thank you andrei.

Thank you for your review.

Adding to sprint

And tagging.

Patch rerolled

Let's postpone this one on the other one. When #1987882: Convert content_translation routes to a new style controller is done we can get back here and ensure that content_translation.pages.inc has been removed.

This already happens in #1987882: Convert content_translation routes to a new style controller

Off of the sprint then.