Follow up for #1331486: Move module_invoke_*() and friends to an Extensions class
Problem/Motivation
https://api.drupal.org/api/drupal/core%21includes%21bootstrap.inc/functi...
is wrong, it says Use drupal_container()->get('module_handler')->moduleExists($hook).
Should be Drupal::moduleHandler()->moduleExists('language')
Proposed resolution
Update doc.
Remaining tasks
TBD
User interface changes
No.
API changes
No.