mojo leveldb: Get profile and leveldb connected to DOMStorageContext.

components/filesystem/lock_table.h

 // Copyright 2016 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.
 
 #ifndef COMPONENTS_FILESYSTEM_LOCK_TABLE_H_
 #define COMPONENTS_FILESYSTEM_LOCK_TABLE_H_
 
 #include <set>
 
 #include "base/files/file.h"
+#include "base/memory/ref_counted.h"
 
 namespace filesystem {
 
 class FileImpl;
 
 // A table of all locks held by this process. We have one global table owned by
 // the app, but accessible by everything just in case two connections from the
 // same origin try to lock the same file.
-class LockTable {
+class LockTable : public base::RefCounted<LockTable> {
  public:
   LockTable();
-  ~LockTable();
 
   // Locks a file.
   base::File::Error LockFile(FileImpl* file);
 
   // Releases a lock, if there is one.
   base::File::Error UnlockFile(FileImpl* file);
 
   // Removes a path from the list of |locked_files_|. This can be called on
   // files that were never locked, as it is called on all file closes and
   // FileImpl destruction.
   void RemoveFromLockTable(const base::FilePath& path);
 
  private:
+  friend class base::RefCounted<LockTable>;
+  ~LockTable();
+
   // Open, locked files. We keep track of this so we quickly error when we try
   // to double lock a file.
   std::set<base::FilePath> locked_files_;
 
   DISALLOW_COPY_AND_ASSIGN(LockTable);
 };
 
 }  // namespace filesystem
 
 #endif  // COMPONENTS_FILESYSTEM_LOCK_TABLE_H_