Add Unit Tests for `get_comment_pages_count()`. Fix a notice caused when `$wp_query->comments` is not set in that function.

Props mdbitz, markjaquith.
Fixes #20633.


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In `wpdb::db_connect()`, allow the loading of a custom database error template - this is already allowed in `dead_db()`.

In `dead_db()`, move the call to `wp_load_translations_early()` before the inclusion of the `db-error.php` file to allow translation in both locations before the template is loaded.

Props sbruner, kovshenin.
Fixes #25703.


Built from https://develop.svn.wordpress.org/trunk@27056


git-svn-id: http://core.svn.wordpress.org/trunk@26929 1a063a9b-81f0-0310-95a4-ce76da25c4cd
`get_comment()`, `wp_get_post_revision()`, and `get_term()` all used to return by reference. Because of this, `$null` was set to `null` so the return value would be a variable where applicable. This has not been necessary since [21792], so the `$null`s have been removed.

Props toszcze.
Fixes #24768.


Built from https://develop.svn.wordpress.org/trunk@27057


git-svn-id: http://core.svn.wordpress.org/trunk@26930 1a063a9b-81f0-0310-95a4-ce76da25c4cd