Please describe the problem:
When users chooses to expunge Junk folder, Trash is emptied too as a result.

Steps to reproduce:
1. Click Junk Folder
2. Choose Expunge/Ctrl-E
3. Click Trash Folder


Actual results:
Trash will be empty

Expected results:
Trash would NOT be empty, just requested folder, Junk.

Does this happen every time?
Yes

Other information:
I realize Junk is a virtual folder. This MAY occur with other virtual folders
too, but I don't use virtuals. IMHO, emptying TRASH as a result of a
Junk/Expunge is not a good thing to happen since mostly it's SPAM in junk,
whereas, often times, people hold onto TRASH items in case they wish to retrieve
something.