[SyncFS] Crash fix on chrome://syncfs-internals

chrome/browser/sync_file_system/sync_file_system_service.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/sync_file_system/sync_file_system_service.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/format_macros.h"
@@ skipping 530 matching lines @@
 
   v2_remote_service_->DumpDatabase(
       base::Bind(&SyncFileSystemService::DidDumpV2Database,
                  AsWeakPtr(), callback, base::Passed(&list)));
 }
 
 void SyncFileSystemService::DidDumpV2Database(
     const DumpFilesCallback& callback,
     scoped_ptr<base::ListValue> v1list,
     scoped_ptr<base::ListValue> v2list) {
-  DCHECK(v1list);
+  if (!v1list)
+    v1list = make_scoped_ptr(new base::ListValue);
 
   if (v2list) {
     for (base::ListValue::iterator itr = v2list->begin();
          itr != v2list->end();) {
       scoped_ptr<base::Value> item;
       itr = v2list->Erase(itr, &item);
       v1list->Append(item.release());
     }
   }
 
   callback.Run(*v1list);
 }
 
 void SyncFileSystemService::DidGetExtensionStatusMap(
     const ExtensionStatusMapCallback& callback,
     scoped_ptr<RemoteFileSyncService::OriginStatusMap> status_map) {
+  if (!status_map)
+    status_map = make_scoped_ptr(new RemoteFileSyncService::OriginStatusMap);
   if (!v2_remote_service_) {
     callback.Run(*status_map);
     return;
   }
 
   v2_remote_service_->GetOriginStatusMap(
       base::Bind(&SyncFileSystemService::DidGetV2ExtensionStatusMap,
                  AsWeakPtr(),
                  callback,
                  base::Passed(&status_map)));
 }
 
 void SyncFileSystemService::DidGetV2ExtensionStatusMap(
     const ExtensionStatusMapCallback& callback,
     scoped_ptr<RemoteFileSyncService::OriginStatusMap> status_map_v1,
     scoped_ptr<RemoteFileSyncService::OriginStatusMap> status_map_v2) {
   // Merge |status_map_v2| into |status_map_v1|.
-  status_map_v1->insert(status_map_v2->begin(), status_map_v2->end());
+  if (!status_map_v1)
+    status_map_v1 = make_scoped_ptr(new RemoteFileSyncService::OriginStatusMap);
+  if (status_map_v2)
+    status_map_v1->insert(status_map_v2->begin(), status_map_v2->end());
 
   callback.Run(*status_map_v1);
 }
 
 void SyncFileSystemService::SetSyncEnabledForTesting(bool enabled) {
   sync_enabled_ = enabled;
   remote_service_->SetSyncEnabled(sync_enabled_);
   if (v2_remote_service_)
     v2_remote_service_->SetSyncEnabled(sync_enabled_);
 }
@@ skipping 157 matching lines @@
     v2_remote_service_->AddServiceObserver(v2_remote_syncer.get());
     v2_remote_service_->AddFileStatusObserver(this);
     v2_remote_service_->SetRemoteChangeProcessor(local_service_.get());
     v2_remote_service_->SetSyncEnabled(sync_enabled_);
     remote_sync_runners_.push_back(v2_remote_syncer.release());
   }
   return v2_remote_service_.get();
 }
 
 }  // namespace sync_file_system