ServiceWorker: Add support for .skipWaiting and controllerchange event(2/3)

content/browser/service_worker/service_worker_registration.cc

Index: content/browser/service_worker/service_worker_registration.cc
diff --git a/content/browser/service_worker/service_worker_registration.cc b/content/browser/service_worker/service_worker_registration.cc
index 0445f08f7e646ba73497be4257adeb4d6ad008c3..46cfa9aa380f15b58e399b131320884a01935d5a 100644
--- a/content/browser/service_worker/service_worker_registration.cc
+++ b/content/browser/service_worker/service_worker_registration.cc
@@ -154,7 +154,8 @@ void ServiceWorkerRegistration::UnsetVersionInternal(
 void ServiceWorkerRegistration::ActivateWaitingVersionWhenReady() {
   DCHECK(waiting_version());
   should_activate_when_ready_ = true;
-  if (!active_version() || !active_version()->HasControllee())
+  if (!active_version() || !active_version()->HasControllee() ||
+      waiting_version()->skip_waiting())
     ActivateWaitingVersion();
 }
 
@@ -198,7 +199,6 @@ void ServiceWorkerRegistration::AbortPendingClear(
 }
 
 void ServiceWorkerRegistration::OnNoControllees(ServiceWorkerVersion* version) {
-  DCHECK_EQ(active_version(), version);

[falken, 2014/12/01 02:29:59]

I guess this DCHECK can fail now if OnNoControllees gets called by the worker
that was replaced by a skip waiting worker? It would seem in that case we
shouldn't proceed with the rest of the function. Should we instead early-return
if version != active_version()?

[xiang, 2014/12/01 07:20:07]

Thanks for point this out, I think we can remove the listener in
SetVersionInternal(), how do you think?

[falken, 2014/12/01 07:27:52]

Looks right, nice idea.

   if (is_uninstalling_)
     Clear();
   else if (should_activate_when_ready_)
@@ -220,9 +220,8 @@ void ServiceWorkerRegistration::ActivateWaitingVersion() {
     return;  // Activation is no longer relevant.
   }
 
-  // "4. If exitingWorker is not null,
+  // "5. If exitingWorker is not null,
   if (exiting_version.get()) {
-    DCHECK(!exiting_version->HasControllee());
     // TODO(michaeln): should wait for events to be complete
     // "1. Wait for exitingWorker to finish handling any in-progress requests."
     // "2. Terminate exitingWorker."
@@ -233,17 +232,19 @@ void ServiceWorkerRegistration::ActivateWaitingVersion() {
     exiting_version->SetStatus(ServiceWorkerVersion::REDUNDANT);
   }
 
-  // "5. Set serviceWorkerRegistration.activeWorker to activatingWorker."
-  // "6. Set serviceWorkerRegistration.waitingWorker to null."
+  // "6. Set serviceWorkerRegistration.activeWorker to activatingWorker."
+  // "7. Set serviceWorkerRegistration.waitingWorker to null."
   SetActiveVersion(activating_version.get());
 
-  // "7. Run the [[UpdateState]] algorithm passing registration.activeWorker and
+  // "8. Run the [[UpdateState]] algorithm passing registration.activeWorker and
   // "activating" as arguments."
   activating_version->SetStatus(ServiceWorkerVersion::ACTIVATING);
+  // "9. Fire a simple event named controllerchange..."
+  // Notify associated provider hosts to change the controller.
+  if (activating_version->skip_waiting())
+    FOR_EACH_OBSERVER(Listener, listeners_, OnSkippedWaiting(this));
 
-  // TODO(nhiroki): "8. Fire a simple event named controllerchange..."
-
-  // "9. Queue a task to fire an event named activate..."
+  // "10. Queue a task to fire an event named activate..."
   activating_version->DispatchActivateEvent(
       base::Bind(&ServiceWorkerRegistration::OnActivateEventFinished,
                  this, activating_version));