Support modal windows

athena/screen/modal_window_controller.h

Index: athena/screen/modal_window_controller.h
diff --git a/athena/screen/modal_window_controller.h b/athena/screen/modal_window_controller.h
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+++ b/athena/screen/modal_window_controller.h
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+// Copyright 2014 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 ATHENA_SCREEN_MODAL_WINDOW_CONTROLLER_H_
+#define ATHENA_SCREEN_MODAL_WINDOW_CONTROLLER_H_
+
+#include "athena/athena_export.h"
+#include "ui/aura/window_observer.h"
+
+namespace athena {
+
+// ModalWindow controller manages the modal window and
+// its container. This gets created when a modal window is opened
+// and deleted when all modal windows are deleted.
+class ATHENA_EXPORT ModalWindowController : public aura::WindowObserver {
+ public:
+  // Returns the ModalWindowController associated with the container.
+  static ModalWindowController* Get(aura::Window* container);
+
+  explicit ModalWindowController(int container_priority);
+  virtual ~ModalWindowController();
+
+  aura::Window* modal_container() { return modal_container_; }
+
+  bool dimmed() const { return dimmed_; }
+
+ private:
+  // aura::WindowObserver:
+  virtual void OnWindowAdded(aura::Window* child) override;
+  virtual void OnWindowVisibilityChanged(aura::Window* window,
+                                         bool visible) override;
+  virtual void OnWindowBoundsChanged(aura::Window* window,
+                                     const gfx::Rect& old_bounds,
+                                     const gfx::Rect& new_bounds) override;
+  virtual void OnWindowDestroyed(aura::Window* window) override;
+
+  // Tells if the child is not a dimmer window and a child of the modal
+  // container.
+  bool IsChildWindow(aura::Window* child) const;
+
+  void UpdateDimmerWindowBounds();
+
+  // Change dimming state based on the visible window in the container.
+  void UpdateDimming(aura::Window* ignore);
+
+  // Note: changing true -> false will delete the modal_container_.
+  void SetDimmed(bool dimmed);
+
+  aura::Window* modal_container_;  // not owned.
+  aura::Window* dimmer_window_;    // not owned.
+
+  bool dimmed_;
+  DISALLOW_COPY_AND_ASSIGN(ModalWindowController);
+};
+
+}  // namespace athena
+
+#endif  // ATHENA_SCREEN_MODAL_WINDOW_CONTROLLER_H_