splitview: Add animation smoothness metrics for Divider snap animation.

This is a heavy animation as it basically calls into UpdateResize which
resizes both windows (or one window and overview). Also, changes the
animation to use a runner which is synced with the compositor.

Test: none, will update tast-tests
Bug: 1047495
Change-Id: Ic29eb0dd831e7bbc5115268f8c09718b6fc82796
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2254820Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Reviewed-by: Brian White <bcwhite@chromium.org>
Commit-Queue: Sammie Quon <sammiequon@chromium.org>
Cr-Commit-Position: refs/heads/master@{#782707}

ash/wm/splitview/split_view_controller.cc

@@ -10,6 +10,7 @@
 #include "ash/accessibility/accessibility_controller_impl.h"
 #include "ash/display/screen_orientation_controller.h"
 #include "ash/public/cpp/ash_features.h"
+#include "ash/public/cpp/metrics_util.h"
 #include "ash/public/cpp/presentation_time_recorder.h"
 #include "ash/public/cpp/window_properties.h"
 #include "ash/root_window_controller.h"
@@ -47,9 +48,11 @@
 #include "ui/base/class_property.h"
 #include "ui/base/hit_test.h"
 #include "ui/compositor/layer.h"
+#include "ui/compositor/throughput_tracker.h"
 #include "ui/gfx/animation/slide_animation.h"
 #include "ui/gfx/animation/tween.h"
 #include "ui/gfx/transform_util.h"
+#include "ui/views/animation/compositor_animation_runner.h"
 #include "ui/views/widget/widget.h"
 #include "ui/wm/core/coordinate_conversion.h"
 #include "ui/wm/core/shadow_controller.h"
@@ -77,6 +80,11 @@ constexpr float kTwoThirdPositionRatio = 0.67f;
 constexpr float kBlackScrimFadeInRatio = 0.1f;
 constexpr float kBlackScrimOpacity = 0.4f;
 
+// Records the animation smoothness when the divider is released during a resize
+// and animated to a fixed position ratio.
+constexpr char kDividerAnimationSmoothness[] =
+    "Ash.SplitViewResize.AnimationSmoothness.DividerAnimation";
+
 // Histogram names that record presentation time of resize operation with
 // following conditions, a) clamshell split view, empty overview grid,
 // b) clamshell split view, nonempty overview grid, c) tablet split view, one
@@ -281,8 +289,31 @@ class SplitViewController::DividerSnapAnimation
     // in tablet_mode_window_drag_delegate.cc.
     SetSlideDuration(base::TimeDelta::FromMilliseconds(300));
     SetTweenType(gfx::Tween::EASE_IN);
-  }
 
+    aura::Window* window = split_view_controller->left_window()
+                               ? split_view_controller->left_window()
+                               : split_view_controller->right_window();
+    DCHECK(window);
+
+    // |widget| may be null in tests. It will use the default animation
+    // container in this case.
+    views::Widget* widget = views::Widget::GetWidgetForNativeWindow(window);
+    if (!widget)
+      return;
+
+    gfx::AnimationContainer* container = new gfx::AnimationContainer();
+    container->SetAnimationRunner(
+        std::make_unique<views::CompositorAnimationRunner>(widget));
+    SetContainer(container);
+
+    tracker_.emplace(widget->GetCompositor()->RequestNewThroughputTracker());
+    tracker_->Start(
+        metrics_util::ForSmoothness(base::BindRepeating([](int smoothness) {
+          UMA_HISTOGRAM_PERCENTAGE(kDividerAnimationSmoothness, smoothness);
+        })));
+  }
+  DividerSnapAnimation(const DividerSnapAnimation&) = delete;
+  DividerSnapAnimation& operator=(const DividerSnapAnimation&) = delete;
   ~DividerSnapAnimation() override = default;
 
   int ending_position() const { return ending_position_; }
@@ -296,6 +327,9 @@ class SplitViewController::DividerSnapAnimation
 
     split_view_controller_->EndResizeImpl();
     split_view_controller_->EndTabletSplitViewAfterResizingIfAppropriate();
+
+    if (tracker_)
+      tracker_->Stop();
   }
 
   void AnimationProgressed(const gfx::Animation* animation) override {
@@ -311,9 +345,15 @@ class SplitViewController::DividerSnapAnimation
       split_view_controller_->SetWindowsTransformDuringResizing();
   }
 
+  void AnimationCanceled(const gfx::Animation* animation) override {
+    if (tracker_)
+      tracker_->Cancel();
+  }
+
   SplitViewController* split_view_controller_;
   int starting_position_;
   int ending_position_;
+  base::Optional<ui::ThroughputTracker> tracker_;
 };
 
 // static

ash/wm/splitview/split_view_controller.h

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef ASH_WM_SPLITSVIEW_SPLIT_VIEW_CONTROLLER_H_
-#define ASH_WM_SPLITSVIEW_SPLIT_VIEW_CONTROLLER_H_
+#ifndef ASH_WM_SPLITVIEW_SPLIT_VIEW_CONTROLLER_H_
+#define ASH_WM_SPLITVIEW_SPLIT_VIEW_CONTROLLER_H_
 
 #include <limits>
 #include <memory>
@@ -512,4 +512,4 @@ class ASH_EXPORT SplitViewController : public aura::WindowObserver,
 
 }  // namespace ash
 
-#endif  // ASH_WM_SPLITSVIEW_SPLIT_VIEW_CONTROLLER_H_
+#endif  // ASH_WM_SPLITVIEW_SPLIT_VIEW_CONTROLLER_H_

ash/wm/splitview/split_view_divider.h

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef ASH_WM_SPLITSVIEW_SPLIT_VIEW_DIVIDER_H_
-#define ASH_WM_SPLITSVIEW_SPLIT_VIEW_DIVIDER_H_
+#ifndef ASH_WM_SPLITVIEW_SPLIT_VIEW_DIVIDER_H_
+#define ASH_WM_SPLITVIEW_SPLIT_VIEW_DIVIDER_H_
 
 #include <memory>
 
@@ -125,4 +125,4 @@ class ASH_EXPORT SplitViewDivider : public aura::WindowObserver,
 
 }  // namespace ash
 
-#endif  // ASH_WM_SPLITSVIEW_SPLIT_VIEW_DIVIDER_H_
+#endif  // ASH_WM_SPLITVIEW_SPLIT_VIEW_DIVIDER_H_

tools/metrics/histograms/histograms.xml

@@ -10636,6 +10636,17 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
   </summary>
 </histogram>
 
+<histogram name="Ash.SplitViewResize.AnimationSmoothness.DividerAnimation"
+    units="%" expires_after="2021-06-15">
+  <owner>sammiequon@chromium.org</owner>
+  <owner>xdai@chromium.org</owner>
+  <summary>
+    Relative smoothness of animation when releasing the split view divider,
+    recorded when the animation completes. 100% represents ideally smooth 60
+    frames per second.
+  </summary>
+</histogram>
+
 <histogram base="true" name="Ash.SplitViewResize.PresentationTime" units="ms"
     expires_after="2020-12-12">
 <!-- Name completed by histogram_suffixes name="SplitViewResizeModes" -->