Sync FileSystem: disable etag match on duplication recovery.

chrome/browser/sync_file_system/drive_file_sync_client.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/drive_file_sync_client.h"
 
 #include <algorithm>
 #include <functional>
 #include <sstream>
 #include <string>
@@ skipping 819 matching lines @@
     return;
   }
 
   DVLOG(2) << "no conflict detected";
   DCHECK_EQ(1u, entries.size());
   scoped_ptr<google_apis::ResourceEntry> entry(entries.front());
   entries.weak_clear();
   callback.Run(google_apis::HTTP_FOUND, entry.Pass());
 }
 
 void DriveFileSyncClient::DeleteEntries(

[kinuko, 2013/02/12 07:57:30]

This method name might be misnomer?
DeleteDuplicatedEntries maybe?

[tzik, 2013/02/12 11:48:18]

Done.

     ScopedVector<google_apis::ResourceEntry> entries,
     const GDataErrorCallback& callback) {
   DCHECK(CalledOnValidThread());
   DVLOG(2) << "Cleaning up conflict on entry creation";
 
   if (entries.empty()) {
     callback.Run(google_apis::HTTP_SUCCESS);
     return;
   }
 
   scoped_ptr<google_apis::ResourceEntry> entry(entries.back());
   entries.back() = NULL;
   entries.get().pop_back();
 
   drive_service_->DeleteResource(
       entry->resource_id(),
-      entry->etag(),
+      std::string(),  // etag

[kinuko, 2013/02/12 07:57:30]

Can we elaborate this comment?  Like:

// We don't care conflicts here as other clients may be also deleting this file,
so passing an empty etag.
drive_service_->DeleteResource(
    entry->resource_id(),
    std::string(),  // empty etag
    ...

[tzik, 2013/02/12 11:48:18]

Done.

       base::Bind(&DriveFileSyncClient::DidDeleteEntry, AsWeakPtr(),
                  base::Passed(&entries), callback));
 }
 
 void DriveFileSyncClient::DidDeleteEntry(
     ScopedVector<google_apis::ResourceEntry> entries,
     const GDataErrorCallback& callback,
     google_apis::GDataErrorCode error) {
   DCHECK(CalledOnValidThread());
 
   if (error != google_apis::HTTP_SUCCESS &&
       error != google_apis::HTTP_NOT_FOUND) {
     DVLOG(2) << "Error on deleting file: " << error;
     callback.Run(error);
     return;
   }
 
   DVLOG(2) << "Deletion completed";
   DeleteEntries(entries.Pass(), callback);
 }
 
 }  // namespace sync_file_system