[merge to m60] cros: Do not cache |root_window| in ScreenRotationAnimator.

ash/display/display_configuration_controller.cc

 // Copyright 2016 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/display/display_configuration_controller.h"
 
 #include "ash/display/display_animator.h"
 #include "ash/display/display_animator_chromeos.h"
 #include "ash/display/display_util.h"
+#include "ash/display/window_tree_host_manager.h"
 #include "ash/rotator/screen_rotation_animator.h"
+#include "ash/shell.h"
 #include "ash/strings/grit/ash_strings.h"
 #include "base/time/time.h"
 #include "chromeos/system/devicemode.h"
+#include "ui/base/class_property.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/display/display_layout.h"
 #include "ui/display/manager/display_manager.h"
 
+DECLARE_UI_CLASS_PROPERTY_TYPE(ash::ScreenRotationAnimator*);
+
 namespace {
 
 // Specifies how long the display change should have been disabled
 // after each display change operations.
 // |kCycleDisplayThrottleTimeoutMs| is set to be longer to avoid
 // changing the settings while the system is still configurating
 // displays. It will be overriden by |kAfterDisplayChangeThrottleTimeoutMs|
 // when the display change happens, so the actual timeout is much shorter.
 const int64_t kAfterDisplayChangeThrottleTimeoutMs = 500;
 const int64_t kCycleDisplayThrottleTimeoutMs = 4000;
 const int64_t kSetPrimaryDisplayThrottleTimeoutMs = 500;
 
+// A property key to store the ScreenRotationAnimator of the window; Used for
+// screen rotation.
+DEFINE_OWNED_UI_CLASS_PROPERTY_KEY(ash::ScreenRotationAnimator,
+                                   kScreenRotationAnimatorKey,
+                                   nullptr);
+
+aura::Window* GetRootWindow(int64_t display_id) {
+  return ash::Shell::Get()
+      ->window_tree_host_manager()
+      ->GetRootWindowForDisplayId(display_id);
+}
+
 }  // namespace
 
 namespace ash {
 
 class DisplayConfigurationController::DisplayChangeLimiter {
  public:
   DisplayChangeLimiter() : throttle_timeout_(base::Time::Now()) {}
 
   void SetThrottleTimeout(int64_t throttle_ms) {
     throttle_timeout_ =
@@ skipping 127 matching lines @@
 void DisplayConfigurationController::SetPrimaryDisplayIdImpl(
     int64_t display_id) {
   window_tree_host_manager_->SetPrimaryDisplayId(display_id);
   if (display_animator_)
     display_animator_->StartFadeInAnimation();
 }
 
 ScreenRotationAnimator*
 DisplayConfigurationController::GetScreenRotationAnimatorForDisplay(
     int64_t display_id) {
-  auto iter = rotation_animator_map_.find(display_id);
-  if (iter != rotation_animator_map_.end())
-    return iter->second.get();
-
-  auto animator = base::MakeUnique<ScreenRotationAnimator>(display_id);
-  ScreenRotationAnimator* result = animator.get();
-  rotation_animator_map_.insert(
-      std::make_pair(display_id, std::move(animator)));
-  return result;
+  aura::Window* root_window = GetRootWindow(display_id);
+  ScreenRotationAnimator* animator =
+      root_window->GetProperty(kScreenRotationAnimatorKey);
+  if (!animator) {
+    animator = new ScreenRotationAnimator(root_window);
+    root_window->SetProperty(kScreenRotationAnimatorKey, animator);
+  }
+  return animator;
 }
 
 }  // namespace ash