Show multiple entity types on Core taxonomy/term pages, not just 'node'

This is an unfortuante hold over from previous node-centric versions of Drupal. You'll either need to wait for views support or write your own handler to show a list of media items by tag.

Let us try and move this then. This code from http://api.drupal.org/api/drupal/modules!taxonomy!taxonomy.pages.inc/fun... stops us from viewing files by taxonomy terms even they are first class drupal entities when expanded by http://drupal.org/project/file_entity.

<?php
 if ($nids = taxonomy_select_nodes($term->tid, TRUE, variable_get('default_nodes_main', 10))) {
    $nodes = node_load_multiple($nids);
    $build += node_view_multiple($nodes);
    $build['pager'] = array(
      '#theme' => 'pager', 
      '#weight' => 5,
    );
  }
?>

The same goes if you tagg any other entities with term ref.

The following issues have the same problem, but they propose different solutions. Hence, a more explicit title:
- other issue: #1016942: Allow taxonomy/term pages to list multiple entity types
- this issue: #1137558: Show multiple entity types on Core taxonomy/term pages, not just 'node'

Even worse: function taxonomy_select_nodes() reads table taxonomy_index, which only contains references to tids of nodes, not other entities.

function taxonomy_select_nodes($tid, $pager = TRUE, $limit = FALSE, $order = array('t.sticky' => 'DESC', 't.created' => 'DESC')) {
  if (!variable_get('taxonomy_maintain_index_table', TRUE)) {
    return array();
  }
  $query = db_select('taxonomy_index', 't');
  $query->addTag('node_access');
  $query->condition('tid', $tid);
  ...
  $query->addField('t', 'nid');
  $query->addField('t', 'tid');
  ...
  return $query->execute()->fetchCol();
}

This is the issue to add 'entities' to taxonomy_index:
#1040786: Include entities in taxonomy_index

added template headers,
added reference to other issue.

#1016942: Allow taxonomy/term pages to list multiple entity types

added other issue to the list.