Update client side selection state when changing selection model (#20370)

Change-Id: I7fe8c160405a69140cac511c744d89a62c401cca

server/src/main/java/com/vaadin/ui/Grid.java

@@ -5595,6 +5595,10 @@ public class Grid extends AbstractFocusable implements SelectionNotifier,
             if (!SharedUtil.equals(oldSelection, newSelection)) {
                 fireSelectionEvent(oldSelection, newSelection);
             }
+
+            // selection is included in the row data, so the client needs to be
+            // updated
+            datasourceExtension.refreshCache();
         }
     }
 

uitest/src/test/java/com/vaadin/tests/components/grid/basicfeatures/server/GridSelectionTest.java

@@ -426,4 +426,44 @@ public class GridSelectionTest extends GridBasicFeaturesTest {
     private GridRowElement getRow(int i) {
         return getGridElement().getRow(i);
     }
+
+    @Test
+    public void changeSelectionModelSingleToNone() throws Exception {
+        openTestURL();
+
+        setSelectionModelSingle();
+        getGridElement().getCell(0, 0).click();
+        assertTrue("row should become selected", getRow(0).isSelected());
+        setSelectionModelNone();
+        assertFalse("row should become deselected", getRow(0).isSelected());
+        setSelectionModelSingle();
+        assertFalse("row should still be deselected", getRow(0).isSelected());
+        getGridElement().getCell(0, 0).click();
+        assertTrue("row should become selected", getRow(0).isSelected());
+    }
+
+    @Test
+    public void changeSelectionModelMultiToNone() throws Exception {
+        openTestURL();
+
+        setSelectionModelMulti();
+        getGridElement().getCell(0, 0).click();
+        getGridElement().getCell(1, 0).click();
+        getGridElement().getCell(2, 0).click();
+        assertTrue("row should become selected", getRow(0).isSelected());
+        assertTrue("row should become selected", getRow(1).isSelected());
+        assertTrue("row should become selected", getRow(2).isSelected());
+
+        setSelectionModelNone();
+        assertFalse("row should become deselected", getRow(0).isSelected());
+        assertFalse("row should become deselected", getRow(1).isSelected());
+        assertFalse("row should become deselected", getRow(2).isSelected());
+        setSelectionModelMulti();
+        assertFalse("row should still be deselected", getRow(0).isSelected());
+        assertFalse("row should still be deselected", getRow(1).isSelected());
+        assertFalse("row should still be deselected", getRow(2).isSelected());
+
+        getGridElement().getCell(0, 0).click();
+        assertTrue("row should become selected", getRow(0).isSelected());
+    }
 }