Make GetRootWindow() return a Window instead of a RootWindow.

ui/views/corewm/input_method_event_filter.h

Index: ui/views/corewm/input_method_event_filter.h
diff --git a/ui/views/corewm/input_method_event_filter.h b/ui/views/corewm/input_method_event_filter.h
index cb1fae489c5b6ab0707cc5694f0f5eb80c604028..902244c88650870bc9aae0ce9fbcb5b9e567c9fc 100644
--- a/ui/views/corewm/input_method_event_filter.h
+++ b/ui/views/corewm/input_method_event_filter.h
@@ -8,15 +8,12 @@
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
+#include "ui/aura/window.h"
 #include "ui/base/ime/input_method_delegate.h"
 #include "ui/events/event_handler.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/views/views_export.h"
 
-namespace aura {
-class RootWindow;
-}
-
 namespace ui {
 class InputMethod;
 }
@@ -33,7 +30,7 @@ class VIEWS_EXPORT InputMethodEventFilter
   explicit InputMethodEventFilter(gfx::AcceleratedWidget widget);
   virtual ~InputMethodEventFilter();
 
-  void SetInputMethodPropertyInRootWindow(aura::RootWindow* root_window);
+  void SetInputMethodPropertyInRootWindow(aura::Window* root_window);
 
   ui::InputMethod* input_method() const { return input_method_.get(); }
 
@@ -49,9 +46,8 @@ class VIEWS_EXPORT InputMethodEventFilter
 
   scoped_ptr<ui::InputMethod> input_method_;
 
-  // The target root window to which the key event translated by IME will
-  // be dispatched.
-  aura::RootWindow* target_root_window_;
+  // The target dispatcher that will receive translated key events from the IME.
+  aura::WindowEventDispatcher* target_dispatcher_;
 
   DISALLOW_COPY_AND_ASSIGN(InputMethodEventFilter);
 };