Add focus rules for Ash.

ash/wm/ash_focus_rules.cc

Index: ash/wm/ash_focus_rules.cc
===================================================================
--- ash/wm/ash_focus_rules.cc	(revision 0)
+++ ash/wm/ash_focus_rules.cc	(revision 0)
@@ -0,0 +1,50 @@
+// Copyright (c) 2012 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.
+
+#include "ash/wm/ash_focus_rules.h"
+
+#include "ui/aura/window.h"
+
+namespace ash {
+namespace wm {
+
+////////////////////////////////////////////////////////////////////////////////
+// AshFocusRules, public:
+
+AshFocusRules::AshFocusRules() {
+}
+
+AshFocusRules::~AshFocusRules() {
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// AshFocusRules, views::corewm::FocusRules:
+
+bool AshFocusRules::CanActivateWindow(aura::Window* window) {
+  return !!window->parent();
+}
+
+bool AshFocusRules::CanFocusWindow(aura::Window* window) {
+  aura::Window* activatable = GetActivatableWindow(window);
+  return activatable->Contains(window) && window->CanFocus();

[sadrul, 2012/11/30 17:10:13]

Can |activatable| (or |window|) be NULL?

+}
+
+aura::Window* AshFocusRules::GetActivatableWindow(aura::Window* window) {
+  return window;
+}
+
+aura::Window* AshFocusRules::GetFocusableWindow(aura::Window* window) {
+  return window;
+}
+
+aura::Window* AshFocusRules::GetNextActivatableWindow(aura::Window* ignore) {
+  return NULL;
+}
+
+aura::Window* AshFocusRules::GetNextFocusableWindow(aura::Window* ignore) {
+  return GetFocusableWindow(ignore->parent());
+}
+
+}  // namespace wm
+}  // namespace ash