Drop other expanded folders when revealing item

We probably should only drop expanded folders which descend from the current root, but that’s more code and the implemented behavior could be seen as “garbage collection” (keeping the memory of expanded folders low).

Frameworks/OakFileBrowser/src/FSOutlineViewDelegate.mm

@@ -267,6 +267,8 @@ static NSSet* VisibleItems (NSOutlineView* outlineView, FSItem* root, NSMutableS
 	
 	if(expandAncestors)
 	{
+		[expandedURLs removeAllObjects];
+
 		NSMutableSet* ancestors = [NSMutableSet set];
 		NSURL* rootURL = dataSource.rootItem.url;