Revert "Store Vaadin session after each update" (#10112)

This reverts commit 48e202a806.

Also reverts the related release notes update.

all/src/main/templates/release-notes.html

@@ -93,7 +93,6 @@
             <li>The browser time zone can be obtained from WebBrowser if the browser supports it</li>
             <li>AbstractDateField now supports formatting of time zone information</li>
             <li>PushState based navigation support</li>
-            <li>VaadinSession is now stored to the HTTP session at the end of each access to support clustering</li>
             <li>Grid WAI-ARIA support has been improved (aria-sort added)</li>
             <li>Client side ErrorLevel support</li>
             <li>VaadinService, VaadinServlet and VaadinServletService have protected no-args constructors to make DI integrations simpler</li>

server/src/main/java/com/vaadin/server/VaadinSession.java

@@ -1035,10 +1035,6 @@ public class VaadinSession implements HttpSessionBindingListener, Serializable {
                                         + ui.getUIId(),
                                 e);
                     }
-                    // Store session after modifications have been done so that
-                    // Spring Session and possibly other implementations realize
-                    // that something has changed inside the session attribute
-                    service.storeSession(this, session);
                 }
             }
         } finally {

server/src/test/java/com/vaadin/ui/UITest.java

@@ -8,9 +8,7 @@ import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReentrantLock;
 
 import javax.servlet.ServletConfig;
-import javax.servlet.http.HttpSession;
 
-import org.easymock.EasyMock;
 import org.junit.Assert;
 import org.junit.Test;
 import org.mockito.Mockito;
@@ -22,7 +20,6 @@ import com.vaadin.server.VaadinRequest;
 import com.vaadin.server.VaadinServlet;
 import com.vaadin.server.VaadinServletService;
 import com.vaadin.server.VaadinSession;
-import com.vaadin.server.WrappedHttpSession;
 import com.vaadin.server.communication.PushConnection;
 import com.vaadin.shared.communication.PushMode;
 import com.vaadin.util.CurrentInstanceTest;
@@ -178,21 +175,7 @@ public class UITest {
         VaadinServletService service = new VaadinServletService(servlet,
                 deploymentConfiguration);
         MockVaadinSession session = new MockVaadinSession(service);
-        HttpSession mockHttpSession = EasyMock.createMock(HttpSession.class);
-        WrappedHttpSession mockWrappedSession = new WrappedHttpSession(
-                mockHttpSession) {
-            @Override
-            public Object getAttribute(String name) {
-                String lockAttribute = service.getServiceName() + ".lock";
-                if (lockAttribute.equals(name)) {
-                    return session.getLockInstance();
-                } else {
-                    return super.getAttribute(name);
-                }
-            }
-        };
         session.lock();
-        session.refreshTransients(mockWrappedSession, service);
         ui.setSession(session);
         ui.doInit(Mockito.mock(VaadinRequest.class), 1, "foo");
         session.addUI(ui);