Prepares a list of blocks for display on the blocks administration page.
$theme: The machine-readable name of the theme whose blocks should be returned.
An array of blocks, as returned by _block_rehash(), sorted by region in preparation for display on the blocks administration page.
function block_admin_display_prepare_blocks($theme) {
$blocks = _block_rehash($theme);
$compare_theme =& drupal_static('_block_compare:theme');
$compare_theme = $theme;
usort($blocks, '_block_compare');
return $blocks;
}