[Sync] Add history delete directive type

sync/syncable/model_type.cc

Index: sync/syncable/model_type.cc
diff --git a/sync/syncable/model_type.cc b/sync/syncable/model_type.cc
index 83e803cdd58c451f6b8eae1efa8e35e56e156203..dcdb684ccfc84df2c2b77469f60f4577da69c607 100644
--- a/sync/syncable/model_type.cc
+++ b/sync/syncable/model_type.cc
@@ -73,6 +73,9 @@ void AddDefaultFieldValue(ModelType datatype,
     case APP_NOTIFICATIONS:
       specifics->mutable_app_notification();
       break;
+    case HISTORY_DELETE_DIRECTIVES:
+      specifics->mutable_history_delete_directive();
+      break;
     default:
       NOTREACHED() << "No known extension for model type.";
   }
@@ -135,6 +138,9 @@ int GetSpecificsFieldNumberFromModelType(ModelType model_type) {
     case APP_NOTIFICATIONS:
       return sync_pb::EntitySpecifics::kAppNotificationFieldNumber;
       break;
+    case HISTORY_DELETE_DIRECTIVES:
+      return sync_pb::EntitySpecifics::kHistoryDeleteDirectiveFieldNumber;
+      break;
     default:
       NOTREACHED() << "No known extension for model type.";
       return 0;
@@ -144,7 +150,7 @@ int GetSpecificsFieldNumberFromModelType(ModelType model_type) {
   return 0;
 }
 
-// Note: keep this consistent with GetModelType in syncable.cc!
+// Note: keep this consistent with GetModelType in entry.cc!
 ModelType GetModelType(const sync_pb::SyncEntity& sync_entity) {
   DCHECK(!IsRoot(sync_entity));  // Root shouldn't ever go over the wire.
 
@@ -219,6 +225,9 @@ ModelType GetModelTypeFromSpecifics(const sync_pb::EntitySpecifics& specifics) {
   if (specifics.has_app_notification())
     return APP_NOTIFICATIONS;
 
+  if (specifics.has_history_delete_directive())
+    return HISTORY_DELETE_DIRECTIVES;
+
   return UNSPECIFIED;
 }
 
@@ -265,6 +274,8 @@ const char* ModelTypeToString(ModelType model_type) {
       return "Extension settings";
     case APP_NOTIFICATIONS:
       return "App Notifications";
+    case HISTORY_DELETE_DIRECTIVES:
+      return "History Delete Directives";
     default:
       break;
   }
@@ -330,6 +341,8 @@ ModelType ModelTypeFromString(const std::string& model_type_string) {
     return EXTENSION_SETTINGS;
   else if (model_type_string == "App Notifications")
     return APP_NOTIFICATIONS;
+  else if (model_type_string == "History Delete Directives")
+    return HISTORY_DELETE_DIRECTIVES;
   else
     NOTREACHED() << "No known model type corresponding to "
                  << model_type_string << ".";
@@ -398,6 +411,8 @@ std::string ModelTypeToRootTag(ModelType type) {
       return "google_chrome_extension_settings";
     case APP_NOTIFICATIONS:
       return "google_chrome_app_notifications";
+    case HISTORY_DELETE_DIRECTIVES:
+      return "google_chrome_history_delete_directives";
     default:
       break;
   }
@@ -423,6 +438,8 @@ const char kSearchEngineNotificationType[] = "SEARCH_ENGINE";
 const char kSessionNotificationType[] = "SESSION";
 const char kAutofillProfileNotificationType[] = "AUTOFILL_PROFILE";
 const char kAppNotificationNotificationType[] = "APP_NOTIFICATION";
+const char kHistoryDeleteDirectiveNotificationType[] =
+    "HISTORY_DELETE_DIRECTIVE";
 }  // namespace
 
 bool RealModelTypeToNotificationType(ModelType model_type,
@@ -473,6 +490,9 @@ bool RealModelTypeToNotificationType(ModelType model_type,
     case APP_NOTIFICATIONS:
       *notification_type = kAppNotificationNotificationType;
       return true;
+    case HISTORY_DELETE_DIRECTIVES:
+      *notification_type = kHistoryDeleteDirectiveNotificationType;
+      return true;
     default:
       break;
   }
@@ -527,6 +547,9 @@ bool NotificationTypeToRealModelType(const std::string& notification_type,
   } else if (notification_type == kAppNotificationNotificationType) {
     *model_type = APP_NOTIFICATIONS;
     return true;
+  } else if (notification_type == kHistoryDeleteDirectiveNotificationType) {
+    *model_type = HISTORY_DELETE_DIRECTIVES;
+    return true;
   } else {
     *model_type = UNSPECIFIED;
     return false;