diff -r 000000000000 -r 6474c204b198 dom/base/CompositionStringSynthesizer.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/base/CompositionStringSynthesizer.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,44 @@
+/* -*- 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_dom_compositionstringsynthesizer_h__
+#define mozilla_dom_compositionstringsynthesizer_h__
+
+#include "nsICompositionStringSynthesizer.h"
+#include "nsString.h"
+#include "nsWeakReference.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/TextRange.h"
+
+class nsIWidget;
+class nsPIDOMWindow;
+
+namespace mozilla {
+namespace dom {
+
+class CompositionStringSynthesizer MOZ_FINAL :
+  public nsICompositionStringSynthesizer
+{
+public:
+  CompositionStringSynthesizer(nsPIDOMWindow* aWindow);
+  ~CompositionStringSynthesizer();
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSICOMPOSITIONSTRINGSYNTHESIZER
+
+private:
+  nsWeakPtr mWindow; // refers an instance of nsPIDOMWindow
+  nsString mString;
+  nsRefPtr<TextRangeArray> mClauses;
+  TextRange mCaret;
+
+  nsIWidget* GetWidget();
+  void ClearInternal();
+};
+
+} // namespace dom
+} // namespace mozilla
+
+#endif // #ifndef mozilla_dom_compositionstringsynthesizer_h__