Fixed the racy code around the message-only window in base::MessagePumpForUI on Windows.

base/win/message_window.h

 // Copyright 2013 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 REMOTING_HOST_WIN_MESSAGE_WINDOW_H_
-#define REMOTING_HOST_WIN_MESSAGE_WINDOW_H_
+#ifndef BASE_WIN_MESSAGE_WINDOW_H_
+#define BASE_WIN_MESSAGE_WINDOW_H_
 
 #include <windows.h>
 
 #include <string>
 
+#include "base/base_export.h"
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/threading/non_thread_safe.h"
 
-namespace remoting {
+namespace base {
 namespace win {
 
 // Implements a message-only window.
-class MessageWindow : base::NonThreadSafe {
+class BASE_EXPORT MessageWindow : public base::NonThreadSafe {
  public:
   // Handles incoming window messages.
-  class Delegate {
+  class BASE_EXPORT Delegate {
    public:
     virtual ~Delegate() {}
 
     virtual bool HandleMessage(HWND hwnd,
                                UINT message,
                                WPARAM wparam,
                                LPARAM lparam,
                                LRESULT* result) = 0;
   };
 
   MessageWindow();
-  MessageWindow(const std::string& class_name, HINSTANCE instance);
   ~MessageWindow();
 
   // Registers the window class and creates the window. The incoming messages
   // will be handled by |delegate|. |delegate| must outlive |this|.
   bool Create(Delegate* delegate);
 
   HWND hwnd() const { return window_; }
 
  private:
   // Invoked by the OS to process incoming window messages.
   static LRESULT CALLBACK WindowProc(HWND hwnd, UINT message, WPARAM wparam,
                                      LPARAM lparam);
 
   // Atom representing the registered window class.
   ATOM atom_;
 
   // MessageWindow class name.
   std::string class_name_;
 
   // Instance of the module containing the window procedure.
   HINSTANCE instance_;
 
   // Handle of the input window.
   HWND window_;
 
   DISALLOW_COPY_AND_ASSIGN(MessageWindow);
 };
 
 }  // namespace win
-}  // namespace remoting
+}  // namespace base
 
-#endif  // REMOTING_HOST_WIN_MESSAGE_WINDOW_H_
+#endif  // BASE_WIN_MESSAGE_WINDOW_H_