feat(service-worker): handle 'notificationclick' events (#25860)

The previous version did not support the 'notificationclick' event.
Add event handler for the event and provide an observable of
clicked notifications in the SwPush service.

Closes #20956, #22311

PR Close #25860

packages/service-worker/test/integration_spec.ts

@@ -88,6 +88,7 @@ const serverUpdate =
       scope.clients.getMock('default') !.queue.subscribe(msg => { mock.sendMessage(msg); });
 
       mock.messages.subscribe(msg => { scope.handleMessage(msg, 'default'); });
+      mock.messagesClicked.subscribe(msg => { scope.handleMessage(msg, 'default'); });
 
       mock.setupSw();
       reg = mock.mockRegistration !;
@@ -128,5 +129,18 @@ const serverUpdate =
       });
       await gotPushNotice;
     });
+
+    async_it('receives push message click events', async() => {
+      const push = new SwPush(comm);
+      scope.updateServerState(serverUpdate);
+
+      const gotNotificationClick = (async() => {
+        const event = await obsToSinglePromise(push.messagesClicked);
+        expect(event).toEqual({action: 'clicked', notification: {clicked: true}});
+      })();
+
+      await scope.handleClick({clicked: true}, 'clicked');
+      await gotNotificationClick;
+    });
   });
 })();