Title: Fixed filtering views in distributed setup lead to empty views
Level: 1
Component: multisite
Class: fix
Compatible: compat
State: unknown
Version: 1.2.6b1
Date: 1416992290

This fixes an error where filtering a view leads into an empty view, because 
the enforced site filter has the first site preselected, which is not always
the site of the data shown in the view. Now we use the optional site filter
for most views to cleanup this error.
