Tracker: code simplication to hrev47374

We don't need to create a BNode from a BDirectory because BDirectory derives
from BNode! So use the BDirectory we already have as a BNode and get the
node_ref from it so we can pass it into WatchNode().

Sorry for the noise.

src/kits/tracker/DeskWindow.cpp

@@ -170,9 +170,8 @@ LoadAddOnDir(BDirectory directory, BDeskWindow* window,
 		free(name);
 	}
 
-	BNode node(&directory, NULL);
 	node_ref nodeRef;
-	node.GetNodeRef(&nodeRef);
+	directory.GetNodeRef(&nodeRef);
 
 	TTracker::WatchNode(&nodeRef, B_WATCH_DIRECTORY, window);
 }