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

remoting/host/win/host_service.h

Index: remoting/host/win/host_service.h
diff --git a/remoting/host/win/host_service.h b/remoting/host/win/host_service.h
index aa1d9ab5f1505ca988fccb20778a065045631ee2..20b290fbff62dccbf961073f91980b48f45ef58c 100644
--- a/remoting/host/win/host_service.h
+++ b/remoting/host/win/host_service.h
@@ -12,8 +12,8 @@
 #include "base/memory/ref_counted.h"
 #include "base/memory/singleton.h"
 #include "base/synchronization/waitable_event.h"
+#include "base/win/message_window.h"
 #include "net/base/ip_endpoint.h"
-#include "remoting/host/win/message_window.h"
 #include "remoting/host/win/wts_terminal_monitor.h"
 
 class CommandLine;
@@ -28,7 +28,7 @@ class AutoThreadTaskRunner;
 class Stoppable;
 class WtsTerminalObserver;
 
-class HostService : public win::MessageWindow::Delegate,
+class HostService : public base::win::MessageWindow::Delegate,
                     public WtsTerminalMonitor {
  public:
   static HostService* GetInstance();
@@ -70,7 +70,7 @@ class HostService : public win::MessageWindow::Delegate,
   // console application).
   int RunInConsole();
 
-  // win::MessageWindow::Delegate interface.
+  // base::win::MessageWindow::Delegate interface.
   virtual bool HandleMessage(HWND hwnd,
                              UINT message,
                              WPARAM wparam,