r11682: convoi freight list no longer changes after loading/unloading freight

[Nazalassa]

This bug only seems to be present in r11682, after the addition of the "via owner" freight sort mode and the subsequent reorganization of the freight sorting code.

When the freight sort mode is set to "amount" or "via (amount)" (and only when it is in one of these modes), the freight list will not update when freight is loaded/unloaded from a convoi.

Steps to reproduce:

• Find a convoi that transports things. Anything should do.
• Open the convoi's info window and look at the freight shown there.
• Make sure the sort mode is either "amount" or "via (amount)". Otherwise there will be no bug.
• Wait until the convoi arrives at a stop where it should load/unload freight.

Expected results:
The freight listed in the info window should change so as to reflect the contents of the convoi.

Observed results:
The freight list does not change if the sort mode is either "amount" or "via (amount)". (Else it will work normally.)

Notes:
The freight list does change when switching to the Schedule tab, or when changing the freight sorting order. It does not change when switching to the Chart or Vehicle details tab.

This bug does not seem to occur for halts.

[prissi]

Ok, found a wrong assignment in r11683.

[Nazalassa]

Sorry to bring in more bugs: as of r11683, when a convoi's window is opened and closed afterwards, its freight list is no longer shown when it is subsequently reopened.
This seems to also affect halts although it's rather hard to reproduce on them since their freight list gets updated more often.

[prissi]

Sorru, indeed. r11684 should address this as well.