Refactor ModelTypePayloadMap and ObjectIdPayloadMap to StateMaps.

sync/notifier/object_id_state_map.cc

Index: sync/notifier/object_id_state_map.cc
diff --git a/sync/notifier/object_id_state_map.cc b/sync/notifier/object_id_state_map.cc
new file mode 100644
index 0000000000000000000000000000000000000000..2d3b7f782172680c0398b6002cfdb47ddef6361f
--- /dev/null
+++ b/sync/notifier/object_id_state_map.cc
@@ -0,0 +1,59 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "sync/notifier/object_id_state_map.h"
+
+namespace syncer {
+
+ObjectIdSet ObjectIdStateMapToSet(const ObjectIdStateMap& id_state_map) {
+  ObjectIdSet ids;
+  for (ObjectIdStateMap::const_iterator it = id_state_map.begin();
+       it != id_state_map.end(); ++it) {
+    ids.insert(it->first);
+  }
+  return ids;
+}
+
+ObjectIdStateMap ObjectIdSetToStateMap(const ObjectIdSet& ids,
+                                       const std::string& payload) {
+  ObjectIdStateMap id_state_map;
+  for (ObjectIdSet::const_iterator it = ids.begin(); it != ids.end(); ++it) {
+    // TODO(dcheng): Do we need to provide a way to set AckHandle?
+    id_state_map[*it].payload = payload;
+  }
+  return id_state_map;
+}
+
+ModelTypeStateMap ObjectIdStateMapToModelTypeStateMap(
+    const ObjectIdStateMap& id_state_map) {
+  ModelTypeStateMap type_state_map;
+  for (ObjectIdStateMap::const_iterator it = id_state_map.begin();
+       it != id_state_map.end(); ++it) {
+    ModelType model_type;
+    if (!ObjectIdToRealModelType(it->first, &model_type)) {
+      DLOG(WARNING) << "Invalid object ID: "
+                    << ObjectIdToString(it->first);
+      continue;
+    }
+    type_state_map[model_type] = it->second;
+  }
+  return type_state_map;
+}
+
+ObjectIdStateMap ModelTypeStateMapToObjectIdStateMap(
+    const ModelTypeStateMap& type_state_map) {
+  ObjectIdStateMap id_state_map;
+  for (ModelTypeStateMap::const_iterator it = type_state_map.begin();
+       it != type_state_map.end(); ++it) {
+    invalidation::ObjectId id;
+    if (!RealModelTypeToObjectId(it->first, &id)) {
+      DLOG(WARNING) << "Invalid model type " << it->first;
+      continue;
+    }
+    id_state_map[id] = it->second;
+  }
+  return id_state_map;
+}
+
+}  // namespace syncer