Don't crash when trying to create an ExtensionSyncData from invalid SyncData.

chrome/browser/extensions/app_sync_data.cc

 // 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 "chrome/browser/extensions/app_sync_data.h"
 
 #include "chrome/common/extensions/manifest_handlers/app_icon_color_info.h"
 #include "chrome/common/extensions/manifest_handlers/app_launch_info.h"
 #include "extensions/common/extension.h"
 #include "sync/api/sync_data.h"
 #include "sync/protocol/app_specifics.pb.h"
 #include "sync/protocol/sync.pb.h"
 
 namespace extensions {
 
 AppSyncData::AppSyncData() {}
 
-AppSyncData::AppSyncData(const syncer::SyncData& sync_data) {
-  PopulateFromSyncData(sync_data);
-}
-
-AppSyncData::AppSyncData(const syncer::SyncChange& sync_change) {
-  PopulateFromSyncData(sync_change.sync_data());
-  extension_sync_data_.set_uninstalled(
-      sync_change.change_type() == syncer::SyncChange::ACTION_DELETE);
-}
-
 AppSyncData::AppSyncData(const Extension& extension,
                          bool enabled,
                          bool incognito_enabled,
                          bool remote_install,
                          ExtensionSyncData::OptionalBoolean all_urls_enabled,
                          const syncer::StringOrdinal& app_launch_ordinal,
                          const syncer::StringOrdinal& page_ordinal,
                          extensions::LaunchType launch_type)
     : extension_sync_data_(extension,
                            enabled,
                            incognito_enabled,
                            remote_install,
                            all_urls_enabled),
       app_launch_ordinal_(app_launch_ordinal),
       page_ordinal_(page_ordinal),
       launch_type_(launch_type) {
   if (extension.from_bookmark()) {
     bookmark_app_description_ = extension.description();
     bookmark_app_url_ = AppLaunchInfo::GetLaunchWebURL(&extension).spec();
     bookmark_app_icon_color_ = AppIconColorInfo::GetIconColorString(&extension);
   }
 }
 
 AppSyncData::~AppSyncData() {}
 
+// static
+scoped_ptr<AppSyncData> AppSyncData::CreateFromSyncData(
+    const syncer::SyncData& sync_data) {
+  scoped_ptr<AppSyncData> data(new AppSyncData);
+  if (data->PopulateFromSyncData(sync_data))
+    return data.Pass();
+  return NULL;
+}
+
+// static
+scoped_ptr<AppSyncData> AppSyncData::CreateFromSyncChange(
+    const syncer::SyncChange& sync_change) {
+  scoped_ptr<AppSyncData> data(CreateFromSyncData(sync_change.sync_data()));
+  if (!data.get())
+    return NULL;
+
+  data->extension_sync_data_.set_uninstalled(sync_change.change_type() ==
+                                             syncer::SyncChange::ACTION_DELETE);
+  return data.Pass();
+}
+
 syncer::SyncData AppSyncData::GetSyncData() const {
   sync_pb::EntitySpecifics specifics;
   PopulateAppSpecifics(specifics.mutable_app());
 
   return syncer::SyncData::CreateLocalData(extension_sync_data_.id(),
                                    extension_sync_data_.name(),
                                    specifics);
 }
 
 syncer::SyncChange AppSyncData::GetSyncChange(
@@ skipping 25 matching lines @@
   if (!bookmark_app_description_.empty())
     specifics->set_bookmark_app_description(bookmark_app_description_);
 
   if (!bookmark_app_icon_color_.empty())
     specifics->set_bookmark_app_icon_color(bookmark_app_icon_color_);
 
   extension_sync_data_.PopulateExtensionSpecifics(
       specifics->mutable_extension());
 }
 
-void AppSyncData::PopulateFromAppSpecifics(
+bool AppSyncData::PopulateFromAppSpecifics(
     const sync_pb::AppSpecifics& specifics) {
-  extension_sync_data_.PopulateFromExtensionSpecifics(specifics.extension());
+  if (!extension_sync_data_.PopulateFromExtensionSpecifics(
+          specifics.extension()))
+    return false;
 
   app_launch_ordinal_ = syncer::StringOrdinal(specifics.app_launch_ordinal());
   page_ordinal_ = syncer::StringOrdinal(specifics.page_ordinal());
 
   launch_type_ = specifics.has_launch_type()
       ? static_cast<extensions::LaunchType>(specifics.launch_type())
       : LAUNCH_TYPE_INVALID;
 
   bookmark_app_url_ = specifics.bookmark_app_url();
   bookmark_app_description_ = specifics.bookmark_app_description();
   bookmark_app_icon_color_ = specifics.bookmark_app_icon_color();
+  return true;
 }
 
-void AppSyncData::PopulateFromSyncData(const syncer::SyncData& sync_data) {
-  PopulateFromAppSpecifics(sync_data.GetSpecifics().app());
+bool AppSyncData::PopulateFromSyncData(const syncer::SyncData& sync_data) {
+  return PopulateFromAppSpecifics(sync_data.GetSpecifics().app());
 }
 
 }  // namespace extensions