Fix filesystem API file_handlers to work for drive on ChromeOS.

webkit/fileapi/file_system_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_FILE_SYSTEM_CONTEXT_H_
 #define WEBKIT_FILEAPI_FILE_SYSTEM_CONTEXT_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 223 matching lines @@
 
   // For non-cracked isolated and external mount points, returns a FileSystemURL
   // created by cracking |url|. The url is cracked using MountPoints registered
   // as |url_crackers_|. If the url cannot be cracked, returns invalid
   // FileSystemURL.
   //
   // If the original url does not point to an isolated or external filesystem,
   // returns the original url, without attempting to crack it.
   FileSystemURL CrackFileSystemURL(const FileSystemURL& url) const;
 
+  // If the url has underlying file system url, returns its mount type.
+  // Otherwise returns kFileSystemTypeUnknown.
+  FileSystemType GetUnderlyingMountType(const FileSystemURL& url) const;
+
+  // Converts full file path to a virtual path under mount point contained in
+  // one of the url crackers that support the passed mount type.
+  // Returns whether the path can be converted.
+  bool GetVirtualPath(FileSystemType mount_type,
+                      const base::FilePath& full_path,
+                      base::FilePath* virtual_path) const;
+
   // Returns the appropriate FileUtil instance for the given |type|.
   // This may return NULL if it is given an invalid type or the filesystem
   // does not support synchronous file operations.
   FileSystemFileUtil* GetFileUtil(FileSystemType type) const;
 
   scoped_ptr<FileSystemTaskRunners> task_runners_;
 
   scoped_refptr<quota::QuotaManagerProxy> quota_manager_proxy_;
 
   // Regular mount point providers.
@@ skipping 24 matching lines @@
 
 struct DefaultContextDeleter {
   static void Destruct(const FileSystemContext* context) {
     context->DeleteOnCorrectThread();
   }
 };
 
 }  // namespace fileapi
 
 #endif  // WEBKIT_FILEAPI_FILE_SYSTEM_CONTEXT_H_