sync: Move migration signal out of snapshot

chrome/browser/sync/glue/sync_backend_host_impl.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/sync/glue/sync_backend_host_impl.h"
 
 #include "base/command_line.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/invalidation/invalidation_service.h"
 #include "chrome/browser/invalidation/invalidation_service_factory.h"
@@ skipping 584 matching lines @@
 void SyncBackendHostImpl::HandleSyncCycleCompletedOnFrontendLoop(
     const syncer::sessions::SyncSessionSnapshot& snapshot) {
   if (!frontend_)
     return;
   DCHECK_EQ(base::MessageLoop::current(), frontend_loop_);
 
   last_snapshot_ = snapshot;
 
   SDVLOG(1) << "Got snapshot " << snapshot.ToString();
 
-  const syncer::ModelTypeSet to_migrate =
-      snapshot.model_neutral_state().types_needing_local_migration;
-  if (!to_migrate.Empty())
-    frontend_->OnMigrationNeededForTypes(to_migrate);
-
   // Process any changes to the datatypes we're syncing.
   // TODO(sync): add support for removing types.
   if (initialized())
     AddExperimentalTypes();

[Nicolas Zea, 2014/02/12 20:05:18]

Kindda unrelated to this patch, but I wonder if we can move the experiments
handling code to be event driven as well.

 
   if (initialized())
     frontend_->OnSyncCycleCompleted();
 }
 
 void SyncBackendHostImpl::RetryConfigurationOnFrontendLoop(
     const base::Closure& retry_callback) {
   SDVLOG(1) << "Failed to complete configuration, informing of retry.";
   retry_callback.Run();
 }
@@ skipping 10 matching lines @@
 }
 
 void SyncBackendHostImpl::HandleActionableErrorEventOnFrontendLoop(
     const syncer::SyncProtocolError& sync_error) {
   if (!frontend_)
     return;
   DCHECK_EQ(base::MessageLoop::current(), frontend_loop_);
   frontend_->OnActionableError(sync_error);
 }
 
+void SyncBackendHostImpl::HandleMigrationRequestedOnFrontendLoop(
+    syncer::ModelTypeSet types) {
+  if (!frontend_)
+    return;
+  DCHECK_EQ(base::MessageLoop::current(), frontend_loop_);
+  frontend_->OnMigrationNeededForTypes(types);
+}
+
 void SyncBackendHostImpl::OnInvalidatorStateChange(
     syncer::InvalidatorState state) {
   registrar_->sync_thread()->message_loop()->PostTask(
       FROM_HERE,
       base::Bind(&SyncBackendHostCore::DoOnInvalidatorStateChange,
                  core_.get(),
                  state));
 }
 
 void SyncBackendHostImpl::OnIncomingInvalidation(
@@ skipping 92 matching lines @@
 base::MessageLoop* SyncBackendHostImpl::GetSyncLoopForTesting() {
   return registrar_->sync_thread()->message_loop();
 }
 
 }  // namespace browser_sync
 
 #undef SDVLOG
 
 #undef SLOG