My fix for #24272, #23613, File not found when single file in a folder (

#24800)

* Fixed group share searching for members of
multiple group. Issue #11808.

* Fixed group share searching, continued.

Avoid searching for empty group list in getItemSharedWithUser().
Broke tests in previous commit, #12030.

* Simler check for group count.

* Fix for #24783 , described there

* Now it's #24272, 24783 was a duplicate. Previous change was also not very good. Now we don't create ZIP with a single file inside.

apps/files/js/filelist.js

@@ -661,7 +661,7 @@
 		_onClickDownloadSelected: function(event) {
 			var files;
 			var dir = this.getCurrentDirectory();
-			if (this.isAllSelected()) {
+			if (this.isAllSelected() && this.getSelectedFiles().length > 1) {
 				files = OC.basename(dir);
 				dir = OC.dirname(dir) || '/';
 			}