[Sync] Convert DTCs to be not RefCounted and NonThreadSafe.

components/sync/driver/non_ui_model_type_controller.h

Index: components/sync/driver/non_ui_model_type_controller.h
diff --git a/components/sync/driver/non_ui_model_type_controller.h b/components/sync/driver/non_ui_model_type_controller.h
index 8462af2e9497fac108d49bf5d136034cb3d43590..9d5b23dc073492aa1f36a0537fc88981fc3bc8bc 100644
--- a/components/sync/driver/non_ui_model_type_controller.h
+++ b/components/sync/driver/non_ui_model_type_controller.h
@@ -19,16 +19,10 @@ namespace sync_driver_v2 {
 // - RunOnModelThread
 class NonUIModelTypeController : public NonBlockingDataTypeController {
  public:
-  NonUIModelTypeController(
-      const scoped_refptr<base::SingleThreadTaskRunner>& ui_thread,
-      const base::Closure& error_callback,
-      syncer::ModelType model_type,
-      sync_driver::SyncClient* sync_client);
-
-  void RunOnUIThread(const tracked_objects::Location& from_here,
-                     const base::Closure& task) override;
-
- protected:
+  // |dump_stack| is called when an unrecoverable error occurs.
+  NonUIModelTypeController(syncer::ModelType type,
+                           const base::Closure& dump_stack,
+                           sync_driver::SyncClient* sync_client);
   ~NonUIModelTypeController() override;
 
  private: