[USS] Change the place where SharedModelTypeProcessor got created

components/sync_driver/non_blocking_data_type_controller.cc

Index: components/sync_driver/non_blocking_data_type_controller.cc
diff --git a/components/sync_driver/non_blocking_data_type_controller.cc b/components/sync_driver/non_blocking_data_type_controller.cc
index f2996ab1e97325dfd0b5577de28efb704b36a651..a28f35747a87fed20fa1d339f6ec033253de2442 100644
--- a/components/sync_driver/non_blocking_data_type_controller.cc
+++ b/components/sync_driver/non_blocking_data_type_controller.cc
@@ -12,6 +12,8 @@
 #include "base/single_thread_task_runner.h"
 #include "components/sync_driver/backend_data_type_configurer.h"
 #include "components/sync_driver/sync_client.h"
+#include "sync/api/model_type_change_processor.h"
+#include "sync/api/model_type_service.h"
 #include "sync/api/sync_error.h"
 #include "sync/api/sync_merge_result.h"
 #include "sync/internal_api/public/activation_context.h"
@@ -53,11 +55,8 @@ void NonBlockingDataTypeController::LoadModels(
   // Start the type processor on the model thread.
   if (!RunOnModelThread(
           FROM_HERE,
-          base::Bind(
-              &syncer_v2::SharedModelTypeProcessor::OnSyncStarting,
-              type_processor(),
-              base::Bind(&NonBlockingDataTypeController::OnProcessorStarted,
-                         this)))) {
+          base::Bind(&NonBlockingDataTypeController::LoadModelsOnModelThread,
+                     this))) {
     LoadModelsDone(
         UNRECOVERABLE_ERROR,
         syncer::SyncError(FROM_HERE, syncer::SyncError::DATATYPE_ERROR,
@@ -65,6 +64,31 @@ void NonBlockingDataTypeController::LoadModels(
   }
 }
 
+void NonBlockingDataTypeController::LoadModelsOnModelThread() {
+  base::WeakPtr<syncer_v2::ModelTypeService> model_type_service =
+      sync_client_->GetModelTypeServiceForType(type());
+  if (!model_type_service.get()) {
+    LOG(WARNING) << "ModelTypeService destroyed before "
+                    "ModelTypeController was started.";
+    // TODO(gangwu): Add SyncError and then call start_callback with it. also
+    // set an error state to |state_|.
+    return;
+  }
+
+  model_type_service->OnSyncStarting(

[maxbogue, 2016/03/22 21:40:12]

This call should return a ModelTypeChangeProcessor* directly, and that is what
should be static_cast and stored.

[Gang Wu, 2016/03/24 15:56:26]

Done.

+      base::Bind(&NonBlockingDataTypeController::OnProcessorStarted, this));
+
+  syncer_v2::ModelTypeChangeProcessor* model_type_change_processor =
+      model_type_service->change_processor();
+  if (model_type_change_processor == NULL) {

[maxbogue, 2016/03/22 21:40:12]

Just DCHECK.

[Gang Wu, 2016/03/24 15:56:25]

Done.

+    LOG(WARNING) << "Cannot initalize ModelTypeChangeProcessor.";
+    return;
+  }
+  type_processor_ = static_cast<syncer_v2::SharedModelTypeProcessor*>(
+                        model_type_change_processor)
+                        ->AsWeakPtrForUI();
+}
+
 void NonBlockingDataTypeController::LoadModelsDone(
     ConfigureResult result,
     const syncer::SyncError& error) {
@@ -222,31 +246,4 @@ syncer::ModelType NonBlockingDataTypeController::type() const {
   return model_type_;
 }
 
-void NonBlockingDataTypeController::InitializeProcessorOnModelThread() {
-  base::WeakPtr<syncer_v2::ModelTypeService> model_type_service =
-      sync_client_->GetModelTypeServiceForType(type());
-  if (!model_type_service.get()) {
-    LOG(WARNING) << "ModelTypeService destroyed before "
-                    "ModelTypeController was started.";
-    // TODO(gangwu): Add SyncError and then call start_callback with it. also
-    // set an error state to |state_|.
-  }
-
-  scoped_ptr<syncer_v2::SharedModelTypeProcessor> shared_model_type_processor(
-      make_scoped_ptr(new syncer_v2::SharedModelTypeProcessor(
-          type(), model_type_service.get())));
-  type_processor_ = shared_model_type_processor->AsWeakPtrForUI();
-  model_type_service->set_change_processor(
-      std::move(shared_model_type_processor));
-}
-
-void NonBlockingDataTypeController::InitializeProcessor() {
-  DCHECK(BelongsToUIThread());
-  RunOnModelThread(
-      FROM_HERE,
-      base::Bind(
-          &NonBlockingDataTypeController::InitializeProcessorOnModelThread,
-          this));
-}
-
 }  // namespace sync_driver_v2