USS SyncContextProxy / data type activation refactoring

components/sync_driver/non_ui_data_type_controller.h

Index: components/sync_driver/non_ui_data_type_controller.h
diff --git a/components/sync_driver/non_ui_data_type_controller.h b/components/sync_driver/non_ui_data_type_controller.h
index 5550f49ee11a2bf4df4859e5aab7c25cdadb0024..3a999f53c93f8e1944293af8aee2c42a9acfab27 100644
--- a/components/sync_driver/non_ui_data_type_controller.h
+++ b/components/sync_driver/non_ui_data_type_controller.h
@@ -5,8 +5,6 @@
 #ifndef COMPONENTS_SYNC_DRIVER_NON_UI_DATA_TYPE_CONTROLLER_H_
 #define COMPONENTS_SYNC_DRIVER_NON_UI_DATA_TYPE_CONTROLLER_H_
 
-#include <string>
-
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
@@ -48,9 +46,6 @@ class NonUIDataTypeController : public DirectoryDataTypeController {
   // DataTypeController is RefCounted.
   ~NonUIDataTypeController() override;
 
-  // DataTypeController interface.
-  void OnModelLoaded() override;
-
   // Start any dependent services that need to be running before we can
   // associate models. The default implementation is a no-op.
   // Return value:
@@ -99,6 +94,11 @@ class NonUIDataTypeController : public DirectoryDataTypeController {
   // and shutdown, use a factory method to create the SharedChangeProcessor.
   virtual SharedChangeProcessor* CreateSharedChangeProcessor();
 
+  // If the DTC is waiting for models to load, once the models are
+  // loaded the datatype service will call this function on DTC to let
+  // us know that it is safe to start associating.
+  void OnModelLoaded();
+
  private:
 
   // Posted on the backend thread by StartAssociationAsync().