Add second copy request after screen rotation to flatten the layers in animation.

ash/rotator/screen_rotation_animator.h

 // Copyright 2015 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 ASH_ROTATOR_SCREEN_ROTATION_ANIMATOR_H_
 #define ASH_ROTATOR_SCREEN_ROTATION_ANIMATOR_H_
 
 #include <stdint.h>
 
 #include "ash/ash_export.h"
 #include "base/callback_forward.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/observer_list.h"
 #include "ui/display/display.h"
 
+namespace aura {
+class Window;
+}  // namesapce aura
+
 namespace cc {
+class CopyOutputRequest;
 class CopyOutputResult;
 }  // namespace cc
 
 namespace ui {
 class AnimationMetricsReporter;
 class Layer;
+class LayerOwner;
 class LayerTreeOwner;
 }  // namespace ui
 
 namespace ash {
 namespace test {
 class ScreenRotationAnimatorTestApi;
 }  // namespace test
 
 class ScreenRotationAnimatorObserver;
 
@@ skipping 28 matching lines @@
 
  protected:
   using CopyCallback =
       base::Callback<void(std::unique_ptr<cc::CopyOutputResult> result)>;
   struct ScreenRotationRequest {
     ScreenRotationRequest(int64_t id,
                           display::Display::Rotation to_rotation,
                           display::Display::RotationSource from_source)
         : id(id), new_rotation(to_rotation), source(from_source) {}
     int64_t id;
+    display::Display::Rotation old_rotation;
     display::Display::Rotation new_rotation;
     display::Display::RotationSource source;
   };
 
   // This function can be overridden in unit test to test removing external
   // display.
-  virtual CopyCallback CreateAfterCopyCallback(
+  virtual CopyCallback CreateAfterCopyCallbackBeforeRotation(
+      std::unique_ptr<ScreenRotationRequest> rotation_request);
+
+  // This function can be overridden in unit test to test removing external
+  // display.
+  virtual CopyCallback CreateAfterCopyCallbackAfterRotation(
       std::unique_ptr<ScreenRotationRequest> rotation_request);
 
  private:
   friend class ash::test::ScreenRotationAnimatorTestApi;
 
   void StartRotationAnimation(
       std::unique_ptr<ScreenRotationRequest> rotation_request);
 
-  // This is an asynchronous call to request copy output of root layer.
-  void RequestCopyRootLayerAndAnimateRotation(
+  // The code path to start "slow animation". The difference between the "slow"
+  // and "smooth" animation, is that "slow animation" will recreate all the
+  // layers before rotation and use the recreated layers and rotated layers for
+  // cross-fading animation. This is slow by adding multiple layer animation
+  // elements. The "smooth animation" copies the layer output before and after
+  // rotation, and use them for cross-fading animation. The output copy layer
+  // flatten the layer hierarchy and makes the animation smooth.
+  void StartSlowAnimation(
       std::unique_ptr<ScreenRotationRequest> rotation_request);
 
-  // The callback in |RequestCopyRootLayerAndAnimateRotation()|.
-  void OnRootLayerCopiedBeforeRotation(
+  // A wrapper to call |display_manager| to set screen rotation and rotate the
+  // |old_layer_tree| to the |old_rotation|.
+  void SetRotation(display::Display::Rotation old_rotation,
+                   display::Display::Rotation new_rotation,
+                   display::Display::RotationSource source);
+
+  // This is an asynchronous call to request copy output of root layer.
+  void RequestCopyScreenRotationContainerLayer(
+      std::unique_ptr<cc::CopyOutputRequest> copy_output_request);
+
+  // The callback in |RequestCopyScreenRotationContainerLayer()| before screen
+  // rotation.
+  void OnScreenRotationContainerLayerCopiedBeforeRotation(
       std::unique_ptr<ScreenRotationRequest> rotation_request,
       std::unique_ptr<cc::CopyOutputResult> result);
 
-  // Recreates all |root_window| layers.
-  void CreateOldLayerTree();
+  // The callback in |RequestCopyScreenRotationContainerLayer()| after screen
+  // rotation.
+  void OnScreenRotationContainerLayerCopiedAfterRotation(
+      std::unique_ptr<ScreenRotationRequest> rotation_request,
+      std::unique_ptr<cc::CopyOutputResult> result);
 
-  // Requests a copy of |root_window| root layer output.
-  void CopyOldLayerTree(std::unique_ptr<cc::CopyOutputResult> result);
+  // Recreates all |root_window| layers and their layer tree owner.
+  void CreateOldLayerTreeForSlowAnimation();
+
+  // Creates a new layer and its layer tree owner from |CopyOutputResult|.
+  std::unique_ptr<ui::LayerTreeOwner> CopyLayerTree(
+      std::unique_ptr<cc::CopyOutputResult> result);
 
   // Note: Only call this function when the |old_layer_tree_owner_| is set up
   // properly.
   // Sets the screen orientation to |new_rotation| and animate the change. The
   // animation will rotate the initial orientation's layer towards the new
   // orientation through |rotation_degrees| while fading out, and the new
   // orientation's layer will be rotated in to the |new_orientation| through
   // |rotation_degrees| arc.
   void AnimateRotation(std::unique_ptr<ScreenRotationRequest> rotation_request);
 
-  void set_disable_animation_timers_for_test(bool disable_timers);
+  void set_disable_animation_timers_for_test(bool disable_timers) {
+    disable_animation_timers_for_test_ = disable_timers;
+  }
 
   void StopAnimating();
 
   // The id of the display to rotate.
   int64_t display_id_;
 
   // For current slow rotation animation, there are two states |ROTATING| and
   // |IDLE|. For the smooth rotation animation, we need to send copy request
   // and get copy result before animating.
   enum ScreenRotationState {
     COPY_REQUESTED,
     ROTATING,
     IDLE,
   };
   ScreenRotationState screen_rotation_state_;
 
   // Rotation request id, used to ignore copy request callback if we decide to
   // cancel the previous rotation request.
   int64_t rotation_request_id_;
 
   std::unique_ptr<ui::AnimationMetricsReporter> metrics_reporter_;
   // Only set in unittest to disable animation timers.
   bool disable_animation_timers_for_test_;
   base::ObserverList<ScreenRotationAnimatorObserver>
       screen_rotation_animator_observers_;
   std::unique_ptr<ui::LayerTreeOwner> old_layer_tree_owner_;
+  std::unique_ptr<ui::LayerTreeOwner> new_layer_tree_owner_;
+  std::unique_ptr<ui::LayerOwner> black_mask_layer_owner_;
   std::unique_ptr<ScreenRotationRequest> last_pending_request_;
+  bool has_switch_ash_enable_smooth_screen_rotation_;
+  aura::Window* root_window_;
+  ui::Layer* screen_rotation_container_layer_;
   base::WeakPtrFactory<ScreenRotationAnimator> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ScreenRotationAnimator);
 };
 
 }  // namespace ash
 
 #endif  // ASH_ROTATOR_SCREEN_ROTATION_ANIMATOR_H_