Don't emit documentActivated signal during shutdown
The ProjectTreeView
bug mentioned in the added comment occurs only if
the Auto-Select Current Document option in Projects tool view is on.
locateCurrentDocument()
is called and selects the corresponding
ProjectTreeView
row whenever the documentActivated
signal is emitted
then. Afterwards ProjectTreeView::saveState()
saves the selected row.
ProjectTreeView::restoreState()
restores the saved row on next KDevelop
start.