mojo filesystem: Further clean ups.

components/filesystem/file_system_app.h

 // Copyright 2015 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_FILE_SYSTEM_APP_H_
 #define COMPONENTS_FILESYSTEM_FILE_SYSTEM_APP_H_
 
 #include "base/macros.h"
 #include "components/filesystem/directory_impl.h"
 #include "components/filesystem/file_system_impl.h"
 #include "components/filesystem/lock_table.h"
 #include "components/filesystem/public/interfaces/file_system.mojom.h"
 #include "mojo/services/tracing/public/cpp/tracing_impl.h"
 #include "mojo/shell/public/cpp/interface_factory.h"
 #include "mojo/shell/public/cpp/shell_client.h"
 
 namespace mojo {
 class Shell;
 }
 
 namespace filesystem {
 
 class FileSystemApp : public mojo::ShellClient,
                       public mojo::InterfaceFactory<FileSystem> {
  public:
   FileSystemApp();
   ~FileSystemApp() override;
 
  private:
+  // Gets the system specific toplevel profile directory.
+  static base::FilePath GetUserDataDir();
+
   // |mojo::ShellClient| override:
   void Initialize(mojo::Shell* shell, const std::string& url,
                   uint32_t id) override;
   bool AcceptConnection(mojo::Connection* connection) override;
 
   // |InterfaceFactory<Files>| implementation:
   void Create(mojo::Connection* connection,
               mojo::InterfaceRequest<FileSystem> request) override;
 
   mojo::Shell* shell_;
   mojo::TracingImpl tracing_;
 
   scoped_ptr<LockTable> lock_table_;
 
   DISALLOW_COPY_AND_ASSIGN(FileSystemApp);
 };
 
 }  // namespace filesystem
 
 #endif  // COMPONENTS_FILESYSTEM_FILE_SYSTEM_APP_H_