Call CloseClipboard() with anonymous access token.

remoting/host/clipboard_win.cc

 // 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.
 
 #include "remoting/host/clipboard.h"
 
 #include <windows.h>
 
 #include "base/basictypes.h"
 #include "base/bind.h"
@@ skipping 14 matching lines @@
 // A scoper class that opens and closes the clipboard.
 // This class was adapted from the ScopedClipboard class in
 // ui/base/clipboard/clipboard_win.cc.
 class ScopedClipboard {
  public:
   ScopedClipboard() : opened_(false) {
   }
 
   ~ScopedClipboard() {
     if (opened_) {
+      // CloseClipboard() must be called with anonymous access token. See
+      // crbug.com/441834 .
+      BOOL result = ::ImpersonateAnonymousToken(::GetCurrentThread());
+      CHECK(result);

[Wez, 2014/12/12 19:25:36]

nit: I think it'd be acceptable to just CHECK(ApiCall()) in this case.

[Sergey Ulanov, 2014/12/12 19:34:00]

Side effects inside DCHECKs are often hard to debug. It's not a problem for
CHECK, but still I think it's better to avoid this pattern, e.g. in case this
CHECK gets replaced with DCHECK. 

       ::CloseClipboard();
+      ::RevertToSelf();

[Wez, 2014/12/12 19:25:36]

CHECK this as well?

[Sergey Ulanov, 2014/12/12 19:34:00]

Done.

     }
   }
 
   bool Init(HWND owner) {
     const int kMaxAttemptsToOpenClipboard = 5;
     const base::TimeDelta kSleepTimeBetweenAttempts =
         base::TimeDelta::FromMilliseconds(5);
 
     if (opened_) {
       NOTREACHED();
@@ skipping 223 matching lines @@
   }
 
   return false;
 }
 
 scoped_ptr<Clipboard> Clipboard::Create() {
   return make_scoped_ptr(new ClipboardWin());
 }
 
 }  // namespace remoting