cros: Adjust hotseat and shelf animation durations

When the hotseat is enabled, animate the shelf and hotseat at the same
speed as the minimize/maximize animation.

Bug: 1028387
Change-Id: I5fae2038258b3353776bd283950509ec53d26e2a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1935492Reviewed-by: Alex Newcomer <newcomer@chromium.org>
Reviewed-by: Manu Cornet <manucornet@chromium.org>
Auto-Submit: Alex Newcomer <newcomer@chromium.org>
Commit-Queue: Manu Cornet <manucornet@chromium.org>
Cr-Commit-Position: refs/heads/master@{#718946}

ash/public/cpp/shelf_config.h

@@ -94,6 +94,9 @@ class ASH_EXPORT ShelfConfig : public TabletModeObserver,
   // The duration of the hotseat background animations in ms.
   base::TimeDelta hotseat_background_animation_duration() const;
 
+  // The duration of the shelf show/hide animation in ms.
+  base::TimeDelta shelf_animation_duration() const;
+
   // The extra padding added to status area tray buttons on the shelf.
   int status_area_hit_region_padding() const;
 

ash/shelf/shelf_config.cc

@@ -182,7 +182,15 @@ int ShelfConfig::home_button_edge_spacing() const {
 }
 
 base::TimeDelta ShelfConfig::hotseat_background_animation_duration() const {
-  return base::TimeDelta::FromMilliseconds(350);
+  // This matches the duration of the maximize/minimize animation.
+  return base::TimeDelta::FromMilliseconds(300);
+}
+
+base::TimeDelta ShelfConfig::shelf_animation_duration() const {
+  if (chromeos::switches::ShouldShowShelfHotseat())
+    return hotseat_background_animation_duration();
+
+  return base::TimeDelta::FromMilliseconds(200);
 }
 
 int ShelfConfig::status_area_hit_region_padding() const {

ash/shelf/shelf_layout_manager.cc

@@ -91,9 +91,6 @@ constexpr float kDefaultShelfOpacity = 1.0f;
 // Delay before showing the shelf. This is after the mouse stops moving.
 constexpr int kAutoHideDelayMS = 200;
 
-// Duration of the animation to show or hide the shelf.
-constexpr int kAnimationDurationMS = 200;
-
 // To avoid hiding the shelf when the mouse transitions from a message bubble
 // into the shelf, the hit test area is enlarged by this amount of pixels to
 // keep the shelf from hiding.
@@ -1395,7 +1392,7 @@ void ShelfLayoutManager::UpdateBoundsAndOpacity(
       shelf_animation_setter.AddObserver(hide_animation_observer_.get());
 
     if (animate) {
-      auto duration = base::TimeDelta::FromMilliseconds(kAnimationDurationMS);
+      auto duration = ShelfConfig::Get()->shelf_animation_duration();
       shelf_animation_setter.SetTransitionDuration(duration);
       shelf_animation_setter.SetTweenType(gfx::Tween::EASE_OUT);
       shelf_animation_setter.SetPreemptionStrategy(