diff -r 000000000000 -r 6474c204b198 widget/windows/WinIMEHandler.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/widget/windows/WinIMEHandler.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,131 @@
+/* -*- 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 WinIMEHandler_h_
+#define WinIMEHandler_h_
+
+#include "nscore.h"
+#include "nsIWidget.h"
+#include <windows.h>
+#include <inputscope.h>
+
+#define NS_WM_IMEFIRST WM_IME_SETCONTEXT
+#define NS_WM_IMELAST  WM_IME_KEYUP
+
+class nsWindow;
+
+namespace mozilla {
+namespace widget {
+
+struct MSGResult;
+
+/**
+ * IMEHandler class is a mediator class.  On Windows, there are two IME API
+ * sets: One is IMM which is legacy API set. The other is TSF which is modern
+ * API set. By using this class, non-IME handler classes don't need to worry
+ * that we're in which mode.
+ */
+class IMEHandler MOZ_FINAL
+{
+public:
+  static void Initialize();
+  static void Terminate();
+
+  /**
+   * Returns TSF related native data.
+   */
+  static void* GetNativeData(uint32_t aDataType);
+
+  /**
+   * ProcessRawKeyMessage() message is called before calling TranslateMessage()
+   * and DispatchMessage().  If this returns true, the message is consumed.
+   * Then, caller must not perform TranslateMessage() nor DispatchMessage().
+   */
+  static bool ProcessRawKeyMessage(const MSG& aMsg);
+
+  /**
+   * When the message is not needed to handle anymore by the caller, this
+   * returns true.  Otherwise, false.
+   */
+  static bool ProcessMessage(nsWindow* aWindow, UINT aMessage,
+                             WPARAM& aWParam, LPARAM& aLParam,
+                             MSGResult& aResult);
+
+  /**
+   * When there is a composition, returns true.  Otherwise, false.
+   */
+  static bool IsComposing();
+
+  /**
+   * When there is a composition and it's in the window, returns true.
+   * Otherwise, false.
+   */
+  static bool IsComposingOn(nsWindow* aWindow);
+
+  /**
+   * Notifies IME of the notification (a request or an event).
+   */
+  static nsresult NotifyIME(nsWindow* aWindow,
+                            const IMENotification& aIMENotification);
+
+  /**
+   * Returns update preferences.
+   */
+  static nsIMEUpdatePreference GetUpdatePreference();
+
+  /**
+   * Returns IME open state on the window.
+   */
+  static bool GetOpenState(nsWindow* aWindow);
+
+  /**
+   * Called when the window is destroying.
+   */
+  static void OnDestroyWindow(nsWindow* aWindow);
+
+  /**
+   * Called when nsIWidget::SetInputContext() is called before the window's
+   * InputContext is modified actually.
+   */
+  static void SetInputContext(nsWindow* aWindow,
+                              InputContext& aInputContext,
+                              const InputContextAction& aAction);
+
+  /**
+   * Associate or disassociate IME context to/from the aWindow.
+   */
+  static void AssociateIMEContext(nsWindow* aWindow, bool aEnable);
+
+  /**
+   * Called when the window is created.
+   */
+  static void InitInputContext(nsWindow* aWindow, InputContext& aInputContext);
+
+#ifdef DEBUG
+  /**
+   * Returns true when current keyboard layout has IME.  Otherwise, false.
+   */
+  static bool CurrentKeyboardLayoutHasIME();
+#endif // #ifdef DEBUG
+
+private:
+#ifdef NS_ENABLE_TSF
+  static decltype(SetInputScopes)* sSetInputScopes;
+  static void SetInputScopeForIMM32(nsWindow* aWindow,
+                                    const nsAString& aHTMLInputType);
+  static bool sIsInTSFMode;
+  // If sIMMEnabled is false, any IME messages are not handled in TSF mode.
+  // Additionally, IME context is always disassociated from focused window.
+  static bool sIsIMMEnabled;
+  static bool sPluginHasFocus;
+
+  static bool IsTSFAvailable() { return (sIsInTSFMode && !sPluginHasFocus); }
+#endif // #ifdef NS_ENABLE_TSF
+};
+
+} // namespace widget
+} // namespace mozilla
+
+#endif // #ifndef WinIMEHandler_h_