Fix some migration-related bugs

chrome/browser/sync/backend_migrator.cc

Index: chrome/browser/sync/backend_migrator.cc
diff --git a/chrome/browser/sync/backend_migrator.cc b/chrome/browser/sync/backend_migrator.cc
index f17ee992c0ef5d5e919cacf36c922a0942421b2e..306afeb5eaf136f84c1c281cb626bfb1dbda90bb 100644
--- a/chrome/browser/sync/backend_migrator.cc
+++ b/chrome/browser/sync/backend_migrator.cc
@@ -28,12 +28,12 @@ MigrationObserver::~MigrationObserver() {}
 BackendMigrator::BackendMigrator(const std::string& name,
                                  sync_api::UserShare* user_share,
                                  ProfileSyncService* service,
-                                 DataTypeManager* manager)
+                                 DataTypeManager* manager,
+                                 const base::Closure &migration_done_callback)
     : name_(name), user_share_(user_share), service_(service),
       manager_(manager), state_(IDLE),
-      weak_ptr_factory_(ALLOW_THIS_IN_INITIALIZER_LIST(this)) {
-  registrar_.Add(this, chrome::NOTIFICATION_SYNC_CONFIGURE_DONE,
-                 content::Source<DataTypeManager>(manager_));
+      weak_ptr_factory_(ALLOW_THIS_IN_INITIALIZER_LIST(this)),
+      migration_done_callback_(migration_done_callback) {
 }
 
 BackendMigrator::~BackendMigrator() {
@@ -120,22 +120,18 @@ void BackendMigrator::RestartMigration() {
   }
 }
 
-void BackendMigrator::Observe(int type,
-                              const content::NotificationSource& source,
-                              const content::NotificationDetails& details) {
-  DCHECK_EQ(chrome::NOTIFICATION_SYNC_CONFIGURE_DONE, type);
+void BackendMigrator::OnConfigureDone(
+    const DataTypeManager::ConfigureResult& result) {
   if (state_ == IDLE)
     return;
 
   // |manager_|'s methods aren't re-entrant, and we're notified from
   // them, so post a task to avoid problems.
-  SDVLOG(1) << "Posting OnConfigureDone from Observer";
+  SDVLOG(1) << "Posting OnConfigureDoneImpl";
   MessageLoop::current()->PostTask(
       FROM_HERE,
-      base::Bind(&BackendMigrator::OnConfigureDone,
-                 weak_ptr_factory_.GetWeakPtr(),
-                 *content::Details<DataTypeManager::ConfigureResult>(
-                     details).ptr()));
+      base::Bind(&BackendMigrator::OnConfigureDoneImpl,
+                 weak_ptr_factory_.GetWeakPtr(), result));
 }
 
 namespace {
@@ -157,7 +153,7 @@ syncable::ModelTypeSet GetUnsyncedDataTypes(sync_api::UserShare* user_share) {
 
 }  // namespace
 
-void BackendMigrator::OnConfigureDone(
+void BackendMigrator::OnConfigureDoneImpl(
     const DataTypeManager::ConfigureResult& result) {
   SDVLOG(1) << "OnConfigureDone with requested types "
             << ModelTypeSetToString(result.requested_types)
@@ -221,6 +217,9 @@ void BackendMigrator::OnConfigureDone(
     SDVLOG(1) << "BackendMigrator: Migration complete for: "
               << syncable::ModelTypeSetToString(to_migrate_);
     to_migrate_.Clear();
+
+    if (!migration_done_callback_.is_null())
+      migration_done_callback_.Run();
   }
 }