fix(selection): properly update selectAll flag based on current selection

Author: ivanvoznyakovsky

Diff for: src/features/selection/js/selection.js

@@ -464,10 +464,11 @@
             return;
           }
 
+          var selectedRows;
           if (!multiSelect && !selected) {
             service.clearSelectedRows(grid, evt);
           } else if (!multiSelect && selected) {
-            var selectedRows = service.getSelectedRows(grid);
+            selectedRows = service.getSelectedRows(grid);
             if (selectedRows.length > 1) {
               selected = false; // Enable reselect of the row
               service.clearSelectedRows(grid, evt);
@@ -480,9 +481,11 @@
             row.setSelected(!selected);
             if (row.isSelected === true) {
               grid.selection.lastSelectedRow = row;
-            } else {
-              grid.selection.selectAll = false;
             }
+
+            selectedRows = service.getSelectedRows(grid);
+            grid.selection.selectAll = grid.rows.length === selectedRows.length;
+
             grid.api.selection.raise.rowSelectionChanged(row, evt);
           }
         },