Add RevokeFileSystem back to IsolatedContext

webkit/fileapi/isolated_context.h

 // 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.
 
 #ifndef WEBKIT_FILEAPI_ISOLATED_CONTEXT_H_
 #define WEBKIT_FILEAPI_ISOLATED_CONTEXT_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 83 matching lines @@
   // Registers a new isolated filesystem for a given |path| of filesystem
   // |type| filesystem and returns a new filesystem ID.
   // |path| must be an absolute path which has no parent references ('..').
   // If |register_name| is non-null and has non-empty string the path is
   // registered as the given |register_name|, otherwise it is populated
   // with the name internally assigned to the path.
   std::string RegisterFileSystemForPath(FileSystemType type,
                                         const FilePath& path,
                                         std::string* register_name);
 
+  // Revokes the filesystem |filesystem_id|
+  // Returns false if the |filesystem_id| is not (no longer) registered.
+  bool RevokeFileSystem(const std::string& filesystem_id);
+
   // Revokes all filesystem(s) registered for the given path.
   // This is assumed to be called when the registered path becomes
   // globally invalid, e.g. when a device for the path is detached.
   //
   // Note that this revokes the filesystem no matter how many references it has.
   // It is ok to call this for the path that has no associated filesystems.
   // Note that this only works for the filesystems registered by
   // |RegisterFileSystemForPath|.
   void RevokeFileSystemByPath(const FilePath& path);
 
@@ skipping 88 matching lines @@
 
   typedef std::map<std::string, Instance*> IDToInstance;
 
   // Reverse map from registered path to IDs.
   typedef std::map<FilePath, std::set<std::string> > PathToID;
 
   // Obtain an instance of this class via GetInstance().
   IsolatedContext();
   ~IsolatedContext();
 
+  // Unregisters a file system of given |filesystem_id|. Must be called with
+  // lock_ held.  Returns true if the file system is unregistered.
+  bool UnregisterFileSystem(const std::string& filesystem_id);
+
   // Returns a new filesystem_id.  Called with lock.
   std::string GetNewFileSystemId() const;
 
   // This lock needs to be obtained when accessing the instance_map_.
   mutable base::Lock lock_;
 
   IDToInstance instance_map_;
   PathToID path_to_id_map_;
 
   DISALLOW_COPY_AND_ASSIGN(IsolatedContext);
 };
 
 }  // namespace fileapi
 
 #endif  // WEBKIT_FILEAPI_ISOLATED_CONTEXT_H_