Revert "ash: Make power button menu animation faster."

This reverts commit afe2cfbc.

Reason for revert: compile fail on linux-chromeos-dbg

Original change's description:
> ash: Make power button menu animation faster.
> 
> Bug: 826063
> Change-Id: I1930da3effd7952d2019e480048778075a0bcd58
> Reviewed-on: https://chromium-review.googlesource.com/981686
> Commit-Queue: Min Chen <minch@chromium.org>
> Reviewed-by: Dan Erat <derat@chromium.org>
> Reviewed-by: Qiang Xu <warx@google.com>
> Cr-Commit-Position: refs/heads/master@{#546960}

TBR=derat@chromium.org,minch@chromium.org,warx@google.com

Change-Id: I1e1e7937ce2ff174c37f96ef50370d464bdfe86a
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 826063
Reviewed-on: https://chromium-review.googlesource.com/986724Reviewed-by: Peter Mayo <petermayo@chromium.org>
Commit-Queue: Peter Mayo <petermayo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#546980}

ash/system/power/power_button_menu_screen_view.cc

@@ -72,8 +72,8 @@ class PowerButtonMenuScreenView::PowerButtonMenuBackgroundView
     animation.AddObserver(this);
     animation.SetTweenType(show ? gfx::Tween::EASE_IN_2
                                 : gfx::Tween::FAST_OUT_LINEAR_IN);
-    animation.SetTransitionDuration(
-        PowerButtonMenuView::kMenuAnimationDuration);
+    animation.SetTransitionDuration(base::TimeDelta::FromMilliseconds(
+        PowerButtonMenuView::kAnimationTimeoutMs));
 
     layer()->SetOpacity(show ? kPowerButtonMenuOpacity : 0.f);
   }

ash/system/power/power_button_menu_view.cc

@@ -55,7 +55,8 @@ void PowerButtonMenuView::ScheduleShowHideAnimation(bool show) {
   animation.AddObserver(this);
   animation.SetTweenType(show ? gfx::Tween::EASE_IN
                               : gfx::Tween::FAST_OUT_LINEAR_IN);
-  animation.SetTransitionDuration(kMenuAnimationDuration);
+  animation.SetTransitionDuration(
+      base::TimeDelta::FromMilliseconds(kAnimationTimeoutMs));
 
   layer()->SetOpacity(show ? 1.0f : 0.f);
 

ash/system/power/power_button_menu_view.h

@@ -21,9 +21,8 @@ class ASH_EXPORT PowerButtonMenuView : public views::View,
                                        public views::ButtonListener,
                                        public ui::ImplicitAnimationObserver {
  public:
-  // The duration of showing or dismissing power button menu animation.
-  static constexpr base::TimeDelta kMenuAnimationDuration =
-      base::TimeDelta::FromMilliseconds(250);
+  // The duration of the animation to show or hide the power button menu view.
+  static constexpr int kAnimationTimeoutMs = 500;
 
   // Distance of the menu animation transform.
   static constexpr int kMenuViewTransformDistanceDp = 16;