Merge Compositor's ScrollbarAnimationControllers into single class

cc/input/scrollbar_animation_controller.cc

Index: cc/input/scrollbar_animation_controller.cc
diff --git a/cc/input/scrollbar_animation_controller.cc b/cc/input/scrollbar_animation_controller.cc
index dd4b6dac8665b458fd053abf32de443bb13c4b6b..49d24920a2e4134bdbf9c6c553211c997d5b33c5 100644
--- a/cc/input/scrollbar_animation_controller.cc
+++ b/cc/input/scrollbar_animation_controller.cc
@@ -11,11 +11,37 @@
 
 namespace cc {
 
+std::unique_ptr<ScrollbarAnimationController>
+ScrollbarAnimationController::CreateScrollbarAnimationControllerAndroid(
+    int scroll_layer_id,
+    ScrollbarAnimationControllerClient* client,
+    base::TimeDelta delay_before_starting,
+    base::TimeDelta resize_delay_before_starting,
+    base::TimeDelta fade_duration) {
+  return base::WrapUnique(new ScrollbarAnimationController(
+      scroll_layer_id, client, delay_before_starting,
+      resize_delay_before_starting, fade_duration));
+}
+
+std::unique_ptr<ScrollbarAnimationController>
+ScrollbarAnimationController::CreateScrollbarAnimationControllerAuraOverlay(
+    int scroll_layer_id,
+    ScrollbarAnimationControllerClient* client,
+    base::TimeDelta delay_before_starting,
+    base::TimeDelta resize_delay_before_starting,
+    base::TimeDelta fade_duration,
+    base::TimeDelta thinning_duration) {
+  return base::WrapUnique(new ScrollbarAnimationController(
+      scroll_layer_id, client, delay_before_starting,
+      resize_delay_before_starting, fade_duration, thinning_duration));
+}
+
 ScrollbarAnimationController::ScrollbarAnimationController(
     int scroll_layer_id,
     ScrollbarAnimationControllerClient* client,
     base::TimeDelta delay_before_starting,
-    base::TimeDelta resize_delay_before_starting)
+    base::TimeDelta resize_delay_before_starting,
+    base::TimeDelta fade_duration)
     : client_(client),
       delay_before_starting_(delay_before_starting),
       resize_delay_before_starting_(resize_delay_before_starting),
@@ -23,21 +49,78 @@ ScrollbarAnimationController::ScrollbarAnimationController(
       scroll_layer_id_(scroll_layer_id),
       currently_scrolling_(false),
       scroll_gesture_has_scrolled_(false),
+      opacity_(0.0f),
+      fade_duration_(fade_duration),
+      need_thinning_animation_(false),
       weak_factory_(this) {
+  ApplyOpacityToScrollbars(0.0f);
+}
+
+ScrollbarAnimationController::ScrollbarAnimationController(
+    int scroll_layer_id,
+    ScrollbarAnimationControllerClient* client,
+    base::TimeDelta delay_before_starting,
+    base::TimeDelta resize_delay_before_starting,
+    base::TimeDelta fade_duration,
+    base::TimeDelta thinning_duration)
+    : client_(client),
+      delay_before_starting_(delay_before_starting),
+      resize_delay_before_starting_(resize_delay_before_starting),
+      is_animating_(false),
+      scroll_layer_id_(scroll_layer_id),
+      currently_scrolling_(false),
+      scroll_gesture_has_scrolled_(false),
+      opacity_(0.0f),
+      fade_duration_(fade_duration),
+      need_thinning_animation_(true),
+      weak_factory_(this) {
+  vertical_controller_ = SingleScrollbarAnimationControllerThinning::Create(
+      scroll_layer_id, ScrollbarOrientation::VERTICAL, client,
+      thinning_duration);
+  horizontal_controller_ = SingleScrollbarAnimationControllerThinning::Create(
+      scroll_layer_id, ScrollbarOrientation::HORIZONTAL, client,
+      thinning_duration);
+  ApplyOpacityToScrollbars(0.0f);
 }
 
 ScrollbarAnimationController::~ScrollbarAnimationController() {}
 
+ScrollbarSet ScrollbarAnimationController::Scrollbars() const {
+  return client_->ScrollbarsFor(scroll_layer_id_);
+}
+
 SingleScrollbarAnimationControllerThinning&
 ScrollbarAnimationController::GetScrollbarAnimationController(
     ScrollbarOrientation orientation) const {
-  DCHECK(NeedThinningAnimation());
+  DCHECK(need_thinning_animation_);
   if (orientation == ScrollbarOrientation::VERTICAL)
     return *(vertical_controller_.get());
   else
     return *(horizontal_controller_.get());
 }
 
+void ScrollbarAnimationController::StartAnimation() {
+  delayed_scrollbar_fade_.Cancel();
+  is_animating_ = true;
+  last_awaken_time_ = base::TimeTicks();
+  client_->SetNeedsAnimateForScrollbarAnimation();
+}
+
+void ScrollbarAnimationController::StopAnimation() {
+  delayed_scrollbar_fade_.Cancel();
+  is_animating_ = false;
+}
+
+void ScrollbarAnimationController::PostDelayedAnimationTask(bool on_resize) {
+  base::TimeDelta delay =
+      on_resize ? resize_delay_before_starting_ : delay_before_starting_;
+  delayed_scrollbar_fade_.Reset(
+      base::Bind(&ScrollbarAnimationController::StartAnimation,
+                 weak_factory_.GetWeakPtr()));
+  client_->PostDelayedScrollbarAnimationTask(delayed_scrollbar_fade_.callback(),
+                                             delay);
+}
+
 bool ScrollbarAnimationController::Animate(base::TimeTicks now) {
   bool animated = false;
 
@@ -53,7 +136,7 @@ bool ScrollbarAnimationController::Animate(base::TimeTicks now) {
     animated = true;
   }
 
-  if (NeedThinningAnimation()) {
+  if (need_thinning_animation_) {
     animated |= vertical_controller_->Animate(now);
     animated |= horizontal_controller_->Animate(now);
   }
@@ -61,18 +144,10 @@ bool ScrollbarAnimationController::Animate(base::TimeTicks now) {
   return animated;
 }
 
-bool ScrollbarAnimationController::ScrollbarsHidden() const {
-  return false;
-}
-
-bool ScrollbarAnimationController::NeedThinningAnimation() const {
-  return false;
-}
-
 float ScrollbarAnimationController::AnimationProgressAtTime(
     base::TimeTicks now) {
   base::TimeDelta delta = now - last_awaken_time_;
-  float progress = delta.InSecondsF() / Duration().InSecondsF();
+  float progress = delta.InSecondsF() / fade_duration_.InSecondsF();
   return std::max(std::min(progress, 1.f), 0.f);
 }
 
@@ -80,28 +155,55 @@ void ScrollbarAnimationController::DidScrollBegin() {
   currently_scrolling_ = true;
 }
 
+void ScrollbarAnimationController::RunAnimationFrame(float progress) {
+  ApplyOpacityToScrollbars(1.f - progress);
+  client_->SetNeedsRedrawForScrollbarAnimation();
+  if (progress == 1.f)
+    StopAnimation();
+}
+
 void ScrollbarAnimationController::DidScrollUpdate(bool on_resize) {
+  if (need_thinning_animation_ && Captured())
+    return;
+
   StopAnimation();
 
   // As an optimization, we avoid spamming fade delay tasks during active fast
   // scrolls.  But if we're not within one, we need to post every scroll update.
-  if (!currently_scrolling_)
-    PostDelayedAnimationTask(on_resize);
-  else
+  if (!currently_scrolling_) {
+    // We don't fade out scrollbar if they need thinning animation and mouse is
+    // near.
+    if (!need_thinning_animation_ || !mouse_is_near_any_scrollbar())
+      PostDelayedAnimationTask(on_resize);
+  } else {
     scroll_gesture_has_scrolled_ = true;
+  }
+
+  ApplyOpacityToScrollbars(1);
+
+  if (need_thinning_animation_) {
+    vertical_controller_->UpdateThumbThicknessScale();
+    horizontal_controller_->UpdateThumbThicknessScale();
+  }
 }
 
 void ScrollbarAnimationController::DidScrollEnd() {
-  if (scroll_gesture_has_scrolled_) {
-    PostDelayedAnimationTask(false);
-    scroll_gesture_has_scrolled_ = false;
-  }
+  bool has_scrolled = scroll_gesture_has_scrolled_;
+  scroll_gesture_has_scrolled_ = false;
 
   currently_scrolling_ = false;
+
+  // We don't fade out scrollbar if they need thinning animation and mouse is
+  // near.
+  if (need_thinning_animation_ && mouse_is_near_any_scrollbar())
+    return;
+
+  if (has_scrolled)
+    PostDelayedAnimationTask(false);
 }
 
 void ScrollbarAnimationController::DidMouseDown() {
-  if (!NeedThinningAnimation() || ScrollbarsHidden())
+  if (!need_thinning_animation_ || ScrollbarsHidden())
     return;
 
   vertical_controller_->DidMouseDown();
@@ -109,7 +211,7 @@ void ScrollbarAnimationController::DidMouseDown() {
 }
 
 void ScrollbarAnimationController::DidMouseUp() {
-  if (!NeedThinningAnimation())
+  if (!need_thinning_animation_)
     return;
 
   vertical_controller_->DidMouseUp();
@@ -120,7 +222,7 @@ void ScrollbarAnimationController::DidMouseUp() {
 }
 
 void ScrollbarAnimationController::DidMouseLeave() {
-  if (!NeedThinningAnimation())
+  if (!need_thinning_animation_)
     return;
 
   vertical_controller_->DidMouseLeave();
@@ -135,7 +237,7 @@ void ScrollbarAnimationController::DidMouseLeave() {
 void ScrollbarAnimationController::DidMouseMoveNear(
     ScrollbarOrientation orientation,
     float distance) {
-  if (!NeedThinningAnimation())
+  if (!need_thinning_animation_)
     return;
 
   GetScrollbarAnimationController(orientation).DidMouseMoveNear(distance);
@@ -146,64 +248,66 @@ void ScrollbarAnimationController::DidMouseMoveNear(
   if (mouse_is_near_any_scrollbar()) {
     ApplyOpacityToScrollbars(1);
     StopAnimation();
-  } else if (!animating_fade()) {
+  } else if (!is_animating_) {
     PostDelayedAnimationTask(false);
   }
 }
 
 bool ScrollbarAnimationController::mouse_is_over_scrollbar(
     ScrollbarOrientation orientation) const {
-  DCHECK(NeedThinningAnimation());
+  DCHECK(need_thinning_animation_);
   return GetScrollbarAnimationController(orientation).mouse_is_over_scrollbar();
 }
 
 bool ScrollbarAnimationController::mouse_is_near_scrollbar(
     ScrollbarOrientation orientation) const {
-  DCHECK(NeedThinningAnimation());
+  DCHECK(need_thinning_animation_);
   return GetScrollbarAnimationController(orientation).mouse_is_near_scrollbar();
 }
 
 bool ScrollbarAnimationController::mouse_is_near_any_scrollbar() const {
-  DCHECK(NeedThinningAnimation());
+  DCHECK(need_thinning_animation_);
   return vertical_controller_->mouse_is_near_scrollbar() ||
          horizontal_controller_->mouse_is_near_scrollbar();
 }
 
-bool ScrollbarAnimationController::Captured() const {
-  DCHECK(NeedThinningAnimation());
-  return vertical_controller_->captured() || horizontal_controller_->captured();
+bool ScrollbarAnimationController::ScrollbarsHidden() const {
+  return opacity_ == 0.0f;
 }
 
-void ScrollbarAnimationController::PostDelayedAnimationTask(bool on_resize) {
-  base::TimeDelta delay =
-      on_resize ? resize_delay_before_starting_ : delay_before_starting_;
-  delayed_scrollbar_fade_.Reset(
-      base::Bind(&ScrollbarAnimationController::StartAnimation,
-                 weak_factory_.GetWeakPtr()));
-  client_->PostDelayedScrollbarAnimationTask(delayed_scrollbar_fade_.callback(),
-                                             delay);
+bool ScrollbarAnimationController::Captured() const {
+  DCHECK(need_thinning_animation_);
+  return vertical_controller_->captured() || horizontal_controller_->captured();
 }
 
-void ScrollbarAnimationController::StartAnimation() {
-  delayed_scrollbar_fade_.Cancel();
-  is_animating_ = true;
-  last_awaken_time_ = base::TimeTicks();
-  client_->SetNeedsAnimateForScrollbarAnimation();
-}
+void ScrollbarAnimationController::ApplyOpacityToScrollbars(float opacity) {
+  for (ScrollbarLayerImplBase* scrollbar : Scrollbars()) {
+    if (!scrollbar->is_overlay_scrollbar())
+      continue;
+    float effective_opacity = scrollbar->CanScrollOrientation() ? opacity : 0;
+    PropertyTrees* property_trees =
+        scrollbar->layer_tree_impl()->property_trees();
+    // If this method is called during LayerImpl::PushPropertiesTo, we may not
+    // yet have valid layer_id_to_effect_node_index entries as property trees
+    // are pushed after layers during activation. We can skip updating opacity
+    // in that case as we are only registering a scrollbar and because opacity
+    // will be overwritten anyway when property trees are pushed.
+    if (property_trees->IsInIdToIndexMap(PropertyTrees::TreeType::EFFECT,
+                                         scrollbar->id())) {
+      property_trees->effect_tree.OnOpacityAnimated(
+          effective_opacity,
+          property_trees->layer_id_to_effect_node_index[scrollbar->id()],
+          scrollbar->layer_tree_impl());
+    }
+  }
 
-void ScrollbarAnimationController::StopAnimation() {
-  delayed_scrollbar_fade_.Cancel();
-  is_animating_ = false;
-}
+  bool previouslyVisible = opacity_ > 0.0f;
+  bool currentlyVisible = opacity > 0.0f;
 
-ScrollbarSet ScrollbarAnimationController::Scrollbars() const {
-  return client_->ScrollbarsFor(scroll_layer_id_);
-}
+  opacity_ = opacity;
 
-void ScrollbarAnimationController::set_mouse_move_distance_for_test(
-    float distance) {
-  vertical_controller_->set_mouse_move_distance_for_test(distance);
-  horizontal_controller_->set_mouse_move_distance_for_test(distance);
+  if (previouslyVisible != currentlyVisible)
+    client_->DidChangeScrollbarVisibility();
 }
 
 }  // namespace cc