feature_filter
Description:
Runs a filter against all features of the plugins in the registry and returns a GList with the results.
If the first flag is set, only the first match is returned (as a list with a single object).
Parameters:
| this |
registry to query |
| filter |
the filter to use |
| first |
only return first match |
| user_data |
user data passed to the filter function |