wm: Use AnimationThroughputReporter for hide metric

Bug: 1021774
Change-Id: I8b0d4044403df50de63471aa38872f46f2225053
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2271014Reviewed-by: Sadrul Chowdhury <sadrul@chromium.org>
Commit-Queue: Xiyuan Xia <xiyuan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#784157}

ui/wm/core/window_animations.cc

@@ -9,10 +9,10 @@
 #include <algorithm>
 #include <memory>
 
+#include "base/bind.h"
 #include "base/check_op.h"
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
-#include "base/lazy_instance.h"
 #include "base/macros.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/notreached.h"
@@ -23,7 +23,7 @@
 #include "ui/aura/window_delegate.h"
 #include "ui/aura/window_observer.h"
 #include "ui/base/class_property.h"
-#include "ui/compositor/animation_metrics_reporter.h"
+#include "ui/compositor/animation_throughput_reporter.h"
 #include "ui/compositor/compositor_observer.h"
 #include "ui/compositor/layer.h"
 #include "ui/compositor/layer_animation_observer.h"
@@ -139,21 +139,24 @@ class HidingWindowAnimationObserverBase : public aura::WindowObserver {
   DISALLOW_COPY_AND_ASSIGN(HidingWindowAnimationObserverBase);
 };
 
-class HidingWindowMetricsReporter : public ui::AnimationMetricsReporter {
- public:
-  HidingWindowMetricsReporter() = default;
-  ~HidingWindowMetricsReporter() override = default;
-
-  void Report(int value) override {
-    UMA_HISTOGRAM_PERCENTAGE("Ash.Window.AnimationSmoothness.Hide", value);
-  }
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(HidingWindowMetricsReporter);
-};
+// TODO(crbug.com/1021774): Find a better home and merge with
+//     ash::metris_util::ForSmoothness.
+using SmoothnessCallback = base::RepeatingCallback<void(int smoothness)>;
+ui::AnimationThroughputReporter::ReportCallback ForSmoothness(
+    SmoothnessCallback callback) {
+  return base::BindRepeating(
+      [](SmoothnessCallback callback,
+         cc::FrameSequenceMetrics::ThroughputData throughput) {
+        const int smoothness = std::floor(100.0f * throughput.frames_produced /
+                                          throughput.frames_expected);
+        callback.Run(smoothness);
+      },
+      std::move(callback));
+}
 
-base::LazyInstance<HidingWindowMetricsReporter>::Leaky g_reporter_hide =
-    LAZY_INSTANCE_INITIALIZER;
+void ReportHideSmoothness(int smoothness) {
+  UMA_HISTOGRAM_PERCENTAGE("Ash.Window.AnimationSmoothness.Hide", smoothness);
+}
 
 }  // namespace
 
@@ -300,8 +303,12 @@ void AnimateHideWindowCommon(aura::Window* window,
 
   // Property sets within this scope will be implicitly animated.
   ScopedHidingAnimationSettings hiding_settings(window);
-  hiding_settings.layer_animation_settings()->SetAnimationMetricsReporter(
-      g_reporter_hide.Pointer());
+
+  // Report animation smoothness for animations created within this scope.
+  ui::AnimationThroughputReporter reporter(
+      hiding_settings.layer_animation_settings()->GetAnimator(),
+      ForSmoothness(base::BindRepeating(&ReportHideSmoothness)));
+
   // Render surface caching may not provide a benefit when animating the opacity
   // of a single layer.
   if (!window->layer()->children().empty())