Add shutdown notification and service refs to SyncServiceObserver.

components/browser_sync/profile_sync_service.cc

Index: components/browser_sync/profile_sync_service.cc
diff --git a/components/browser_sync/profile_sync_service.cc b/components/browser_sync/profile_sync_service.cc
index d95fccdcf275cf30c22f545529571cfd7cd14f2b..7c8ed990729aea51523cadf8ae37b27d87cdb104 100644
--- a/components/browser_sync/profile_sync_service.cc
+++ b/components/browser_sync/profile_sync_service.cc
@@ -713,6 +713,7 @@ void ProfileSyncService::OnRefreshTokensLoaded() {
 void ProfileSyncService::Shutdown() {
   DCHECK(thread_checker_.CalledOnValidThread());
   UnregisterAuthNotifications();
+  NotifyShutdown();

[skym, 2017/01/26 17:00:37]

Having this right before ShutdownImpl(...), which does call NotifyObservers()
worries me a little bit. While I'm suspicious this doesn't break any of the
existing observer's functionality, it does kind of go against the documentation
in sync_service_observer.h.

I think I'd prefer it if you swapped these two, unless there's a reason for this
ordering.

[Steven Holte, 2017/01/26 20:31:47]

Done.

 
   ShutdownImpl(syncer::BROWSER_SHUTDOWN);
   if (sync_error_controller_) {
@@ -854,6 +855,11 @@ void ProfileSyncService::NotifyForeignSessionUpdated() {
     observer.OnForeignSessionUpdated();
 }
 
+void ProfileSyncService::NotifyShutdown() {
+  for (auto& observer : observers_)
+    observer.OnSyncShutdown(this);
+}
+
 void ProfileSyncService::ClearStaleErrors() {
   ClearUnrecoverableError();
   last_actionable_error_ = SyncProtocolError();
@@ -1373,7 +1379,7 @@ void ProfileSyncService::OnConfigureDone(
 
   // Notify listeners that configuration is done.
   for (auto& observer : observers_)
-    observer.OnSyncConfigurationCompleted();
+    observer.OnSyncConfigurationCompleted(this);
 
   DVLOG(1) << "PSS OnConfigureDone called with status: " << configure_status_;
   // The possible status values: