'fields_map' also needs to be regenerated along with 'fields' in post_process_request in web_ui.py

[gpoveda@…]

The TicketFields class in web_ui.py modifies what fields exist for the current ticket. Line 112 specifically updates the 'fields':

data['fields'] = [f for f in data['fields'] if f['name'] in displayed_fields]

Whenever a request processed in this way that changes what ticket fields exist, Trac's 'fields_map' also needs to be regenerated, eg, line 113 should look like:

data['fields_map'] = dict((field['name'], i)
                       for i, field in enumerate(data['fields']))

Not updating the 'fields_map' leads to errors when generating resources that index into the map. Specifically in my situation, it caused the resolution report link at the top of a ticket, eg. (fixed), to be replaced with a report link using my cc field contents, eg. (cm).