service worker: Make sure a redundant version doesn't have controllees

This CL temporary adds some CHECK to make sure that a
ServiceWorkerVersion doesn't have any controllees when it becomes
redundant. These CHECKs will be removed once we identified the cause
of some crashes.

This CL also add DEBUG_ALIAS_FOR_CSTR in
ServiceWorkerVersion::AddControllee() to put how a ServiceWorkerVersion
became redundant on the stack so that we can retrieve the information
from reports.

Bug: 1021718
Change-Id: I5c62e475d85aa327852b72d577faf8c5ccafb53d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2114478Reviewed-by: Makoto Shimazu <shimazu@chromium.org>
Commit-Queue: Kenichi Ishibashi <bashi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#753436}

content/browser/service_worker/service_worker_register_job.cc

@@ -659,6 +659,9 @@ void ServiceWorkerRegisterJob::OnStoreRegistrationComplete(
     // TODO(falken): Move this further down. The spec says to set status to
     // 'redundant' after promoting the new version to .waiting attribute and
     // 'installed' status.
+    // TODO(crbug.com/951571): Remove this once we identified the cause of
+    // crash.
+    CHECK(!registration()->waiting_version()->HasControllee());
     registration()->waiting_version()->SetStatus(
         ServiceWorkerVersion::REDUNDANT);
   }

content/browser/service_worker/service_worker_registration.cc

@@ -505,6 +505,11 @@ void ServiceWorkerRegistration::ActivateWaitingVersion(bool delay) {
       observer.OnSkippedWaiting(this);
   }
 
+  // TODO(crbug.com/951571): Remove this once we identified the cause of crash.
+  if (exiting_version) {
+    CHECK(!exiting_version->HasControllee());
+  }
+
   // "10. Queue a task to fire an event named activate..."
   // The browser could be shutting down. To avoid spurious start worker
   // failures, wait a bit before continuing.

content/browser/service_worker/service_worker_version.cc

@@ -376,6 +376,9 @@ void ServiceWorkerVersion::SetStatus(Status status) {
   } else if (status == REDUNDANT) {
     embedded_worker_->OnWorkerVersionDoomed();
 
+    // TODO(crbug.com/1021718): Remove this check after we identified the cause.
+    CHECK(bfcached_controllee_map_.empty());
+
     // TODO(crbug.com/951571): Remove this once we figured out the cause of
     // invalid controller status.
     redundant_state_callstack_ = base::debug::StackTrace();
@@ -763,6 +766,10 @@ void ServiceWorkerVersion::AddControllee(
 
   // TODO(yuzus, crbug.com/951571): Remove these CHECKs once we figure out the
   // cause of crash.
+  if (status_ == REDUNDANT) {
+    DEBUG_ALIAS_FOR_CSTR(redundant_callstack_str,
+                         redundant_state_callstack_.ToString().c_str(), 1024);
+  }
   CHECK_NE(status_, NEW);
   CHECK_NE(status_, INSTALLING);
   CHECK_NE(status_, INSTALLED);
@@ -951,7 +958,9 @@ void ServiceWorkerVersion::Doom() {
     container_host->NotifyControllerLost();
   }
   // Any controllee this version had should have removed itself.
-  DCHECK(!HasControllee());
+  // TODO(crbug.com/951571): Change to DCHECK once we identified the cause of
+  // crash.
+  CHECK(!HasControllee());
 
   SetStatus(REDUNDANT);
   if (running_status() == EmbeddedWorkerStatus::STARTING ||