Implement new SyncAPI and convert Preferences to it.

chrome/browser/sync/api/sync_change.cc

Index: chrome/browser/sync/api/sync_change.cc
diff --git a/chrome/browser/sync/api/sync_change.cc b/chrome/browser/sync/api/sync_change.cc
new file mode 100644
index 0000000000000000000000000000000000000000..320dd537f2c2066b8260ae6117352955b5c81c61
--- /dev/null
+++ b/chrome/browser/sync/api/sync_change.cc
@@ -0,0 +1,43 @@
+// Copyright (c) 2011 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 "chrome/browser/sync/api/sync_change.h"
+
+SyncChange::SyncChange() : change_type_(ACTION_INVALID) {
+}
+
+SyncChange::SyncChange(SyncChangeType change_type, const SyncData& sync_data)
+    : change_type_(change_type),
+      sync_data_(sync_data) {
+  DCHECK(IsValid());
+}
+
+SyncChange::~SyncChange() {}
+
+bool SyncChange::IsValid() const {
+  if (change_type_ == ACTION_INVALID || !sync_data_.IsValid())
+    return false;
+
+  // Data from the syncer must always have specifics.
+  if (!sync_data_.IsLocal())
+    return (sync_data_.GetDataType() != syncable::UNSPECIFIED);
+
+  // Local changes must always have a tag.
+  if (sync_data_.GetTag().empty())
+    return false;
+
+  // Adds and updates must have valid specifics (checked by GetDataType())
+  if (change_type_ == ACTION_ADD || change_type_ == ACTION_UPDATE)
+    return (sync_data_.GetDataType() != syncable::UNSPECIFIED);
+
+  return true;
+}
+
+SyncChange::SyncChangeType SyncChange::change_type() const {
+  return change_type_;
+}
+
+SyncData SyncChange::sync_data() const {
+  return sync_data_;
+}