directory: don't pass fd to traverseAllIn()

This patch continues the work of the previous patch: don't pass a file
descriptor at all to traverseAllIn().  Since this fd was only used to
report "directory not found" errors, we can easily move that check to
the caller.  This is a great relief, since it removes the dependency
on a client connection from a lot of enumeration functions.

src/tagTracker.c

@@ -60,7 +60,7 @@ int getNumberOfTagItems(int type)
 
 	resetVisitedFlagsInTagTracker(type);
 
-	traverseAllIn(-1, NULL, visit_tag_items, NULL, (void*)(size_t)type);
+	traverseAllIn(NULL, visit_tag_items, NULL, (void*)(size_t)type);
 
 	ret = (int)num_visited[type];
 	resetVisitedFlagsInTagTracker(type);