Remove taxonomy_term_load_parents_all from taxonomy/taxonomy.module

I've removed some extra @todo comment and changed the documentation in the interface.

Applied patch and checked.It works well changing to RTBC.

Can someone attach this issue to the correct CR that announced the replacement of taxonomy_term_load_parents_all

Added link to the the change record: https://www.drupal.org/node/2328205. Changing to RTBC.

1. +++ b/core/modules/forum/src/ForumManagerInterface.php
   @@ -57,16 +57,13 @@ public function getIndex();
   +   * Fetches the parent forums for a given forum.
       *
       * @param int $tid
       *   Term ID.
       *
       * @return array
       *   Array of parent terms.
   

   This documentation now seems out of sync - but it was just wrong before too since it is a public method on an interface. I think we should still be saying that this is just a wrapper.

2. +++ b/core/modules/forum/src/ForumManagerInterface.php
   @@ -57,16 +57,13 @@ public function getIndex();
   -   * @todo remove and inject a service when taxonomy_term_get_parents_all has an
   -   *   object-oriented equivalent.
   

   This @todo should still in exist but in changed from FormManagerInterface::getParents() was just a wrapper to TermStorage::loadAllParents(). We should remove FormManagerInterface::getParents() in 9.x This patch should be adding the deprecated notice to this function and creating the postponed 9.x issue to remove it.

I'm sprinting at DrupalCamp Ghent and we're looking into this issue.
I'll create the issue to remove the getParents() method from the ForumManagerInterface in 9.x, and create a patch with an interdiff for the todo comment.

I just created #2371593: Properly deprecate ForumManagerInterface::getParents()..

Applied the patch and checked the patch. Everything is ok for me.

This looks ready. Thanks!

This issue is a prioritized change (deprecated function removal) as per https://www.drupal.org/core/beta-changes and it's benefits outweigh any disruption. Committed 0f438fa and pushed to 8.0.x. Thanks!