drive: Fills no-parent entiries in "/drive/other".

chrome/browser/chromeos/drive/resource_entry_conversion.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/chromeos/drive/resource_entry_conversion.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/logging.h"
@@ skipping 34 matching lines @@
   entry_proto.set_base_name(util::EscapeUtf8FileName(entry_proto.title()));
 
   entry_proto.set_resource_id(entry.resource_id());
   entry_proto.set_download_url(entry.download_url().spec());
 
   const google_apis::Link* edit_link =
       entry.GetLinkByType(google_apis::Link::LINK_EDIT);
   if (edit_link)
     entry_proto.set_edit_url(edit_link->href().spec());
 
+  // Sets parent Resource ID. On drive.google.com, a file can have multiple
+  // parents or no parent, but we are forcing a tree-shaped structure (i.e. no
+  // multi-parent or zero-parent entries). Therefore the first found "parent" is
+  // used for the entry and if the entry has no parent, we assign a special ID
+  // which represents no-parent entries. Tracked in http://crbug.com/158904.
   const google_apis::Link* parent_link =
       entry.GetLinkByType(google_apis::Link::LINK_PARENT);
   if (parent_link) {
-    // TODO(haruki): Apply mapping from an empty parent to special dummy
-    // directory. See http://crbug.com/174233. Until we implement it,
-    // ChangeListProcessor ignores such "no parent" entries.
     entry_proto.set_parent_resource_id(
         util::ExtractResourceIdFromUrl(parent_link->href()));
   }
+  // Apply mapping from an empty parent to the special dummy directory.
+  if (entry_proto.parent_resource_id().empty())
+    entry_proto.set_parent_resource_id(util::kDriveOtherDirSpecialResourceId);
 
   entry_proto.set_deleted(entry.deleted());
   entry_proto.set_shared_with_me(HasSharedWithMeLabel(entry));
 
   PlatformFileInfoProto* file_info = entry_proto.mutable_file_info();
 
   file_info->set_last_modified(entry.updated_time().ToInternalValue());
   // If the file has never been viewed (last_viewed_time().is_null() == true),
   // then we will set the last_accessed field in the protocol buffer to 0.
   file_info->set_last_accessed(entry.last_viewed_time().ToInternalValue());
@@ skipping 52 matching lines @@
       entry_proto.set_upload_url(upload_link->href().spec());
   } else {
     // Some resource entries don't map into files (i.e. sites).
     return DriveEntryProto();
   }
 
   return entry_proto;
 }
 
 }  // namespace drive