Address @todo in seven_preprocess_fieldset__media_library_widget

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Please include an interdiff with your patch

We can't just add this here, we have to provide backward compatibility and a deprecation in case someone extended this class. We can't add new deprecations in 9.5.x or 10.0.x so this has to go to 10.1.x now.

has not been addressed

Tagging for change record also for the new paramter

Retitling the issue given that Seven has been removed, but Claro has the same code.

Removing Seven tag and self-assigning

Updated IS

Added draft CR and switched to MR-workflow.

Thank you @Spokje for adding the trigger_error.

Reviewing the MR code everything looks clean
Deprecation has been added
Deprecation is being tested
New functions have correct typehints

Ran the test locally without the fix and got

Failed asserting that string matches format description.
--- Expected
+++ Actual
@@ @@
 @expectedDeprecation:
-%A  Calling Drupal\media_library\Plugin\Field\FieldWidget\MediaLibraryWidget::__construct without

Verified that the claro media library widget works fine.

Great job!

Tested manually in Claro and spotted some regressions

• "Show media item weights" button is not styled and is mising the following classes
  .action-link action-link--extrasmall .action-link--icon-show .media-library-widget__toggle-weight
• "Add Media" button is missing the .media-library-open-button class. This one I'm unsure if the class is used anywhere, but even if Claro is internal this should probably be preserved unless there's a compelling reason to get rid of it.

Spokje → closed merge request !3323

This is the plain diff from the 10.1.x: https://git.drupalcode.org/project/drupal/-/merge_requests/3323.diff

Using that on top of a new MR, based on 11.x.

This needs to be re-rolled for Drupal 10.3.6