fix(dashboard): show every folder when a drag springs into Shared

Dragging an item out of a shared folder and holding it over Up, Back or
the Shared crumb opens Shared to drop into a folder there. The people
filter, which now lasts while browsing shared items, could hide those
folders, and its chips can't be pressed mid-drag. A drag arriving in
Shared now sees everyone's folders.

src/gui/src/UI/Dashboard/TabFiles.js

@@ -2911,8 +2911,11 @@ const TabFiles = {
         }
         this.loadingFolder = false;
         // The people filter lasts while the user browses what was shared with
-        // them, so Back out of a shared folder finds it still set.
-        if ( is_owned_by_me(this.currentPath) ) this.sharerFilter = null;
+        // them, so Back out of a shared folder finds it still set. A drag
+        // springing into Shared sees every folder: chips can't be pressed mid-drag.
+        if ( is_owned_by_me(this.currentPath) || (window.an_item_is_being_dragged && ! isSameDirRefresh) ) {
+            this.sharerFilter = null;
+        }
         this.syncSharedViewChrome();
 
         // Update browser URL to reflect current file path (only when Files tab is active)

src/gui/src/UI/Dashboard/TabFiles.test.js

@@ -647,6 +647,22 @@ describe('TabFiles people filter across navigation', () => {
         expect($('.files .row.selected').attr('data-name')).toBe('b');
     });
 
+    it('shows every folder to a drag that springs into Shared', async () => {
+        await TabFiles.renderDirectory(SHARED);
+        await TabFiles.setSharerFilter('bob');
+        await TabFiles.renderDirectory('/bob/b-uid/b');
+
+        window.an_item_is_being_dragged = true;
+        try {
+            await TabFiles.renderDirectory(SHARED);
+        } finally {
+            window.an_item_is_being_dragged = false;
+        }
+
+        expect(TabFiles.sharerFilter).toBeNull();
+        expect(listed()).toEqual(['a', 'b']);
+    });
+
     it("clears once the user goes back to their own files", async () => {
         await TabFiles.renderDirectory(SHARED);
         await TabFiles.setSharerFilter('bob');