Sync: Add a SyncTypePreferenceProvider interface.

chrome/browser/supervised_user/supervised_user_service_factory.cc

Index: chrome/browser/supervised_user/supervised_user_service_factory.cc
diff --git a/chrome/browser/supervised_user/supervised_user_service_factory.cc b/chrome/browser/supervised_user/supervised_user_service_factory.cc
index 70d12bc95373587e2d987a4e8a30e2455fd5a44f..681a40eabb249be1cb0ad677ea0c25218d1816f1 100644
--- a/chrome/browser/supervised_user/supervised_user_service_factory.cc
+++ b/chrome/browser/supervised_user/supervised_user_service_factory.cc
@@ -8,6 +8,7 @@
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/signin/profile_oauth2_token_service_factory.h"
 #include "chrome/browser/supervised_user/supervised_user_service.h"
+#include "chrome/browser/sync/profile_sync_service_factory.h"
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 
 #if defined(ENABLE_EXTENSIONS)
@@ -41,6 +42,7 @@ SupervisedUserServiceFactory::SupervisedUserServiceFactory()
       extensions::ExtensionsBrowserClient::Get()->GetExtensionSystemFactory());
 #endif
   DependsOn(ProfileOAuth2TokenServiceFactory::GetInstance());
+  DependsOn(ProfileSyncServiceFactory::GetInstance());
 }
 
 SupervisedUserServiceFactory::~SupervisedUserServiceFactory() {}