Langcode not set correctly if using interface language.

Problem/Motivation

Create a view and filter the selectable nodes to the current interface text.
The weight is always save to the user preferred langcode when checking the database.
When seeing the view it does not seem to do anything when saving.

Proposed resolution

Set the current interface text as default value instead of null.
Which turn into the user preffered langcode when saving.

Remaining tasks

User interface changes

API changes

Data model changes