[Sync] Make BackendMigrator not wait for full sync cycles

chrome/browser/sync/profile_sync_service.cc

Index: chrome/browser/sync/profile_sync_service.cc
diff --git a/chrome/browser/sync/profile_sync_service.cc b/chrome/browser/sync/profile_sync_service.cc
index 4480774cb8b4e869c4cda223fe9ed6f8d6043f04..48a0b8bf703347af6d7e39e5399599d789aefcf0 100644
--- a/chrome/browser/sync/profile_sync_service.cc
+++ b/chrome/browser/sync/profile_sync_service.cc
@@ -26,7 +26,6 @@
 #include "chrome/browser/net/gaia/token_service.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/browser/profiles/profile.h"
-#include "chrome/browser/sync/backend_migrator.h"
 #include "chrome/browser/sync/engine/configure_reason.h"
 #include "chrome/browser/sync/glue/change_processor.h"
 #include "chrome/browser/sync/glue/data_type_controller.h"
@@ -392,7 +391,7 @@ void ProfileSyncService::InitializeBackend(bool delete_sync_data_folder) {
 }
 
 void ProfileSyncService::CreateBackend() {
-  backend_.reset(new SyncBackendHost(profile_));
+  backend_.reset(new SyncBackendHost(profile_->GetDebugName(), profile_));
 }
 
 bool ProfileSyncService::IsEncryptedDatatypeEnabled() const {
@@ -448,6 +447,9 @@ void ProfileSyncService::Shutdown(bool sync_disabled) {
 
   // Shutdown the migrator before the backend to ensure it doesn't pull a null
   // snapshot.
+  if (migrator_.get()) {
+    migrator_->RemoveMigrationObserver(this);
+  }
   migrator_.reset();
   sync_js_controller_.AttachJsBackend(WeakHandle<JsBackend>());
 
@@ -604,11 +606,11 @@ void ProfileSyncService::OnUnrecoverableError(
   wizard_.Step(SyncSetupWizard::FATAL_ERROR);
 
   NotifyObservers();
-  LOG(ERROR) << "Unrecoverable error detected -- ProfileSyncService unusable."
-      << message;
   std::string location;
   from_here.Write(true, true, &location);
-  LOG(ERROR) << location;
+  LOG(ERROR)
+      << "Unrecoverable error detected at " << location
+      << " -- ProfileSyncService unusable: " << message;
 
   // Shut all data types down.
   MessageLoop::current()->PostTask(FROM_HERE,
@@ -616,6 +618,11 @@ void ProfileSyncService::OnUnrecoverableError(
         &ProfileSyncService::Shutdown, true));
 }
 
+void ProfileSyncService::OnMigrationStateChange() {
+  // Needed by migration integration tests.
+  NotifyObservers();
+}
+
 void ProfileSyncService::OnBackendInitialized(
     const WeakHandle<JsBackend>& js_backend, bool success) {
   if (!success) {
@@ -1227,7 +1234,10 @@ void ProfileSyncService::ConfigureDataTypeManager() {
 
     // We create the migrator at the same time.
     migrator_.reset(
-        new browser_sync::BackendMigrator(this, data_type_manager_.get()));
+        new browser_sync::BackendMigrator(
+            profile_->GetDebugName(),
+            this, data_type_manager_.get()));
+    migrator_->AddMigrationObserver(this);
   }
 
   syncable::ModelTypeSet types;
@@ -1301,6 +1311,14 @@ bool ProfileSyncService::HasPendingBackendMigration() const {
       migrator_->state() != browser_sync::BackendMigrator::IDLE;
 }
 
+syncable::ModelTypeSet
+    ProfileSyncService::GetPendingMigrationTypesForTest() const {
+  return
+      migrator_.get() ?
+      migrator_->GetPendingMigrationTypesForTest() :
+      syncable::ModelTypeSet();
+}
+
 void ProfileSyncService::GetModelSafeRoutingInfo(
     browser_sync::ModelSafeRoutingInfo* out) const {
   if (backend_.get() && backend_initialized_) {