diff -r 000000000000 -r 6474c204b198 widget/windows/TaskbarPreviewButton.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/widget/windows/TaskbarPreviewButton.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,47 @@
+/* vim: se cin sw=2 ts=2 et : */
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef __mozilla_widget_TaskbarPreviewButton_h__
+#define __mozilla_widget_TaskbarPreviewButton_h__
+
+#include <windows.h>
+#include <shobjidl.h>
+#undef LogSeverity // SetupAPI.h #defines this as DWORD
+
+#include <nsITaskbarPreviewButton.h>
+#include <nsAutoPtr.h>
+#include <nsString.h>
+#include <nsWeakReference.h>
+
+namespace mozilla {
+namespace widget {
+
+class TaskbarWindowPreview;
+class TaskbarPreviewButton : public nsITaskbarPreviewButton, public nsSupportsWeakReference
+{
+public: 
+  TaskbarPreviewButton(TaskbarWindowPreview* preview, uint32_t index);
+  virtual ~TaskbarPreviewButton();
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSITASKBARPREVIEWBUTTON
+
+private:
+  THUMBBUTTON&            Button();
+  nsresult                Update();
+
+  nsRefPtr<TaskbarWindowPreview> mPreview;
+  uint32_t                mIndex;
+  nsString                mTooltip;
+  nsCOMPtr<imgIContainer> mImage;
+};
+
+} // namespace widget
+} // namespace mozilla
+
+#endif /* __mozilla_widget_TaskbarPreviewButton_h__ */
+