* Introduce wp_parse_post_content() and use it in setup_postdata(), get_the_content(), and get_the_remaining_content().
* Add a post ID argument to the_content(), get_the_content(), the_remaining_content(), and get_the_remaining_content().
* Pass the post ID to the the_content filter.
* Remove the format_pages global.
* Declare format_content and split_content as vars in WP_Post.
* phpdoc for the the_content filter that documents the new ID argument and denotes it as not-so-portable.

Props gcorne, DrewAPicture, duck_, aaroncampbell
see #24330


git-svn-id: https://core.svn.wordpress.org/trunk@24301 1a063a9b-81f0-0310-95a4-ce76da25c4cd