Count number of origins with data affected by clearing "cookies and site data".

storage/browser/fileapi/file_system_quota_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 "storage/browser/fileapi/file_system_quota_client.h"
 
 #include <algorithm>
 #include <memory>
 
 #include "base/bind.h"
@@ skipping 149 matching lines @@
       FROM_HERE, base::Bind(&GetOriginsForHostOnFileTaskRunner,
                             base::RetainedRef(file_system_context_),
                             storage_type, host, base::Unretained(origins_ptr)),
       base::Bind(&DidGetOrigins, callback, base::Owned(origins_ptr)));
 }
 
 void FileSystemQuotaClient::DeleteOriginData(
     const GURL& origin,
     StorageType type,
     const DeletionCallback& callback) {
+  // TODO? This method only deletes filesytem entries associated with a quota

[msramek, 2017/01/09 12:54:44]

Let's ask FS owners about this.

[dullweber, 2017/01/09 16:05:46]

I created http://crbug.com/679362 for it. 

+  // type but there are much more kinds of filesystems, which don't get deleted?
+  // Maybe use FileSystemContext::DeleteDataForOriginOnFileTaskRunner, which
+  // iterates over all backends?
   FileSystemType fs_type = QuotaStorageTypeToFileSystemType(type);
   DCHECK(fs_type != kFileSystemTypeUnknown);
-
+  LOG(ERROR) << "deleting filesystem entry: " << origin.spec();
   base::PostTaskAndReplyWithResult(
       file_task_runner(), FROM_HERE,
       base::Bind(&DeleteOriginOnFileTaskRunner,
                  base::RetainedRef(file_system_context_), origin, fs_type),
       callback);
 }
 
 bool FileSystemQuotaClient::DoesSupport(
     storage::StorageType storage_type) const {
   FileSystemType type = QuotaStorageTypeToFileSystemType(storage_type);
   DCHECK(type != kFileSystemTypeUnknown);
   return file_system_context_->IsSandboxFileSystem(type);
 }
 
 base::SequencedTaskRunner* FileSystemQuotaClient::file_task_runner() const {
   return file_system_context_->default_file_task_runner();
 }
 
 }  // namespace storage