text input focus: Supports Window::GetFocusedTextInputClient.

ui/aura/window_delegate.h

Index: ui/aura/window_delegate.h
diff --git a/ui/aura/window_delegate.h b/ui/aura/window_delegate.h
index a7a4083b85f6127d5f0c295f403a1ef9addf8d4e..1927ccd4adb11f51e9175903d6ef839082503331 100644
--- a/ui/aura/window_delegate.h
+++ b/ui/aura/window_delegate.h
@@ -25,6 +25,7 @@ class GestureEvent;
 class KeyEvent;
 class Layer;
 class MouseEvent;
+class TextInputClient;
 class Texture;
 class TouchEvent;
 }
@@ -44,6 +45,10 @@ class AURA_EXPORT WindowDelegate : public ui::EventHandler {
   virtual void OnBoundsChanged(const gfx::Rect& old_bounds,
                                const gfx::Rect& new_bounds) = 0;
 
+  // Returns the focused text input client within this window.
+  // This function does not look at child windows.
+  virtual ui::TextInputClient* GetFocusedTextInputClient() = 0;
+
   // Returns the native cursor for the specified point, in window coordinates,
   // or NULL for the default cursor.
   virtual gfx::NativeCursor GetCursor(const gfx::Point& point) = 0;