allow batch deselection when at attachment limit

Signal/src/ViewControllers/PhotoLibrary/ImagePickerController.swift

@@ -156,14 +156,14 @@ class ImagePickerGridController: UICollectionViewController, PhotoLibraryDelegat
             return
         }
 
+        let asset = photoCollectionContents.asset(at: indexPath.item)
+        switch selectionPanGestureMode {
+        case .select:
             guard canSelectAdditionalItems else {
                 showTooManySelectedToast()
                 return
             }
 
-        let asset = photoCollectionContents.asset(at: indexPath.item)
-        switch selectionPanGestureMode {
-        case .select:
             selectedIds.add(asset.localIdentifier)
             collectionView.selectItem(at: indexPath, animated: true, scrollPosition: [])
         case .deselect: