cros: Do not cache |root_window| in ScreenRotationAnimator.

ash/rotator/screen_rotation_animator_unittest.cc

 // Copyright 2017 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/rotator/screen_rotation_animator.h"
 
 #include "ash/ash_switches.h"
 #include "ash/display/window_tree_host_manager.h"
 #include "ash/public/cpp/config.h"
 #include "ash/rotator/screen_rotation_animator_observer.h"
@@ skipping 24 matching lines @@
       .GetActiveRotation();
 }
 
 void SetDisplayRotation(int64_t display_id,
                         display::Display::Rotation rotation) {
   Shell::Get()->display_manager()->SetDisplayRotation(
       display_id, rotation,
       display::Display::RotationSource::ROTATION_SOURCE_USER);
 }
 
+aura::Window* GetRootWindow(int64_t display_id) {
+  return Shell::Get()->window_tree_host_manager()->GetRootWindowForDisplayId(
+      display_id);
+}
+
 class AnimationObserver : public ScreenRotationAnimatorObserver {
  public:
   AnimationObserver() {}
 
   bool notified() const { return notified_; }
 
   void OnScreenRotationAnimationFinished(
       ScreenRotationAnimator* animator) override {
     notified_ = true;
   }
 
  private:
   bool notified_ = false;
 
   DISALLOW_COPY_AND_ASSIGN(AnimationObserver);
 };
 
 class TestScreenRotationAnimator : public ScreenRotationAnimator {
  public:
   TestScreenRotationAnimator(int64_t display_id,
                              const base::Closure& before_callback,
                              const base::Closure& after_callback);
   ~TestScreenRotationAnimator() override {}
 
+  void set_intersect_after_callback(const base::Closure& after_callback) {
+    intersect_after_callback_ = after_callback;
+  }
+
  private:
   CopyCallback CreateAfterCopyCallbackBeforeRotation(
       std::unique_ptr<ScreenRotationRequest> rotation_request) override;
   CopyCallback CreateAfterCopyCallbackAfterRotation(
       std::unique_ptr<ScreenRotationRequest> rotation_request) override;
 
   void IntersectBefore(CopyCallback next_callback,
                        std::unique_ptr<cc::CopyOutputResult> result);
   void IntersectAfter(CopyCallback next_callback,
                       std::unique_ptr<cc::CopyOutputResult> result);
@@ skipping 457 matching lines @@
           base::Unretained(this), "640x480"));
   SetDisplayRotation(display_manager()->GetDisplayAt(1).id(),
                      display::Display::ROTATE_0);
   animator()->Rotate(display::Display::ROTATE_90,
                      display::Display::RotationSource::ROTATION_SOURCE_USER);
   WaitForCopyCallback();
   EXPECT_EQ(1U, display_manager()->GetNumDisplays());
   EXPECT_EQ(secondary_display_id, display_manager()->GetDisplayAt(0).id());
 }
 
+// If the external primary display is removed during a rotation animation. It
+// should work for the next rotation request even the |root_window| changed.
+TEST_F(ScreenRotationAnimatorSmoothAnimationTest,
+       RemoveExternalPrimaryDisplayDuringAnimationChangedRootWindow) {
+  // TODO(wutao): needs GetDisplayInfo http://crbug.com/622480.
+  if (Shell::GetAshConfig() == Config::MASH) {
+    ASSERT_TRUE(ShellPort::Get()->GetDisplayInfo(display_id()).id() !=
+                display_id());
+    return;
+  }
+
+  UpdateDisplay("640x480,800x600");
+  EXPECT_EQ(2U, display_manager()->GetNumDisplays());
+
+  Shell::Get()->window_tree_host_manager()->SetPrimaryDisplayId(
+      display_manager()->GetDisplayAt(1).id());
+  const unsigned int secondary_display_id =
+      display_manager()->GetDisplayAt(0).id();
+  aura::Window* old_root_window = GetRootWindow(secondary_display_id);
+
+  SetScreenRotationAnimator(
+      display_manager()->GetDisplayAt(0).id(), run_loop_->QuitWhenIdleClosure(),
+      base::Bind(
+          &ScreenRotationAnimatorSmoothAnimationTest::RemoveSecondaryDisplay,
+          base::Unretained(this), "640x480"));
+  SetDisplayRotation(display_manager()->GetDisplayAt(0).id(),
+                     display::Display::ROTATE_0);
+  animator()->Rotate(display::Display::ROTATE_90,
+                     display::Display::RotationSource::ROTATION_SOURCE_USER);
+  WaitForCopyCallback();
+  EXPECT_EQ(1U, display_manager()->GetNumDisplays());
+  EXPECT_EQ(secondary_display_id, display_manager()->GetDisplayAt(0).id());
+
+  // Rotate again, should finish.
+  animator()->set_intersect_after_callback(base::Bind(
+      &ScreenRotationAnimatorSmoothAnimationTest::QuitWaitForCopyCallback,
+      base::Unretained(this)));
+  animator()->Rotate(display::Display::ROTATE_270,
+                     display::Display::RotationSource::ROTATION_SOURCE_USER);
+  WaitForCopyCallback();
+  EXPECT_EQ(display::Display::ROTATE_270,
+            GetDisplayRotation(secondary_display_id));
+  aura::Window* new_root_window = GetRootWindow(secondary_display_id);
+  EXPECT_NE(old_root_window, new_root_window);
+}
+
 }  // namespace ash