Partial fix for keyboard occlusion.

ui/keyboard/keyboard_controller.h

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_KEYBOARD_KEYBOARD_CONTROLLER_H_
 #define UI_KEYBOARD_KEYBOARD_CONTROLLER_H_
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/observer_list.h"
 #include "ui/aura/window_observer.h"
 #include "ui/base/ime/input_method_observer.h"
 #include "ui/keyboard/keyboard_export.h"
 
 namespace aura {
 class Window;
 }
-
+namespace gfx {
+class Rect;
+}
 namespace ui {
 class InputMethod;
 class TextInputClient;
 }
 
 namespace keyboard {
 
 class KeyboardControllerProxy;
 class KeyboardLayoutManager;
 
 // Provides control of the virtual keyboard, including providing a container
 // and controlling visibility.
 class KEYBOARD_EXPORT KeyboardController : public ui::InputMethodObserver,
                                            public aura::WindowObserver {
  public:
+  class Observer {

[Ben Goodger (Google), 2013/04/29 16:16:38]

avoid nested classes, they can't be forward-declared

[bryeung, 2013/04/29 18:31:43]

Got it.  Fixed.

+   public:
+    // Called when the keyboard bounds or visibility are about to change.
+    virtual void OnKeyboardBoundsChanging(const gfx::Rect& new_bounds) = 0;
+  };
+
   // Takes ownership of |proxy|.
   explicit KeyboardController(KeyboardControllerProxy* proxy);
   virtual ~KeyboardController();
 
   // Returns the container for the keyboard, which is then owned by the caller.
   // It is the responsibility of the caller to Show() the returned window.
   aura::Window* GetContainerWindow();
 
+  // Management of the observer list.
+  virtual void AddObserver(Observer* observer);
+  virtual void RemoveObserver(Observer* observer);
+
  private:
   // For access to Observer methods for simulation.
   friend class KeyboardControllerTest;
 
   // aura::WindowObserver overrides
   virtual void OnWindowParentChanged(aura::Window* window,
                                      aura::Window* parent) OVERRIDE;
   virtual void OnWindowDestroying(aura::Window* window) OVERRIDE;
 
   // InputMethodObserver overrides
   virtual void OnTextInputStateChanged(
       const ui::TextInputClient* client) OVERRIDE;
   virtual void OnInputMethodDestroyed(
       const ui::InputMethod* input_method) OVERRIDE;
 
   scoped_ptr<KeyboardControllerProxy> proxy_;
   aura::Window* container_;
   ui::InputMethod* input_method_;
 
+  ObserverList<Observer> observer_list_;
+
   DISALLOW_COPY_AND_ASSIGN(KeyboardController);
 };
 
 }  // namespace keyboard
 
 #endif  // UI_KEYBOARD_KEYBOARD_CONTROLLER_H_