Empty block should not have results

The views module allows empty blocks to be hidden altogether. Unfortunately that did not work with tagadelic blocks because even if none of the nodes had tags, the nodes would still be listed in $view->result. This keeps the views module from noticing that the block is empty (see http://drupal.org/node/332762). This patch fixes that by clearing the $view->result array when the block is empty.

This patch is for version 6.x-1, but the issue tracker did not allow me to select that version, hence this issue is incorrectly labelled as 5.x-1.x-dev.