Since Moodle 2.0.2 (MDL-26035), plugins may declare the frankenstyle component in their version.php as in

$plugin->component = 'block_foobar';

This declaration is used to detect if the plugin is installed in the correct location. As we are extending the possibility to install plugins from ZIPs downloaded from moodle.org/plugins, it would be good to have this declaration in all registered plugins (ideally). So the plan is:

1. Add support for checking the component declaration during the ZIP validation in local_plugins
2. Start raising warning if the component is not declared there.
3. Announce and promote the new line in version.php and recommend all maintainers to add it.
4. At some point, escalate the validation rule so that missing $plugin->component is considered as an unacceptable error.