overview: Fix crash when double tap launcher button in overview mode.

Do not allow to show launcher if overview is still animating.

Test: manual
Bug: 905527
Change-Id: I1bc188600d038d4f2df20c224910ae10a8b61e59
Reviewed-on: https://chromium-review.googlesource.com/c/1338235Reviewed-by: Mitsuru Oshima <oshima@chromium.org>
Commit-Queue: Sammie Quon <sammiequon@chromium.org>
Cr-Commit-Position: refs/heads/master@{#608661}

ash/app_list/home_launcher_gesture_handler.cc

@@ -567,6 +567,14 @@ bool HomeLauncherGestureHandler::IsAnimating() {
       return true;
   }
 
+  if (Shell::Get()->window_selector_controller()->IsSelecting() &&
+      Shell::Get()
+          ->window_selector_controller()
+          ->window_selector()
+          ->IsWindowGridAnimating()) {
+    return true;
+  }
+
   return false;
 }
 

ash/wm/overview/window_grid.h

@@ -232,14 +232,16 @@ class ASH_EXPORT WindowGrid : public aura::WindowObserver,
 
   const gfx::Rect bounds() const { return bounds_; }
 
-  views::Widget* drop_target_widget_for_testing() {
-    return drop_target_widget_.get();
-  }
-
   bool should_animate_when_exiting() const {
     return should_animate_when_exiting_;
   }
 
+  views::Widget* shield_widget() { return shield_widget_.get(); }
+
+  views::Widget* drop_target_widget_for_testing() {
+    return drop_target_widget_.get();
+  }
+
  private:
   class ShieldView;
   friend class WindowSelectorTest;

ash/wm/overview/window_selector.cc

@@ -756,6 +756,19 @@ void WindowSelector::OnStartingAnimationComplete(bool canceled) {
   }
 }
 
+bool WindowSelector::IsWindowGridAnimating() {
+  for (auto& grid : grid_list_) {
+    if (grid->shield_widget()
+            ->GetNativeWindow()
+            ->layer()
+            ->GetAnimator()
+            ->is_animating()) {
+      return true;
+    }
+  }
+  return false;
+}
+
 void WindowSelector::OnDisplayRemoved(const display::Display& display) {
   // TODO(flackr): Keep window selection active on remaining displays.
   CancelSelection();

ash/wm/overview/window_selector.h

@@ -220,6 +220,10 @@ class ASH_EXPORT WindowSelector : public display::DisplayObserver,
   // Called when the overview mode starting animation completes.
   void OnStartingAnimationComplete(bool canceled);
 
+  // Returns true if any of the grids in |grid_list_| shield widgets are still
+  // animating.
+  bool IsWindowGridAnimating();
+
   WindowSelectorDelegate* delegate() { return delegate_; }
 
   SplitViewDragIndicators* split_view_drag_indicators() {

ash/wm/overview/window_selector_item.cc

@@ -610,7 +610,6 @@ void WindowSelectorItem::UpdateYPositionAndOpacity(
 
   for (auto& layer_and_offset : animation_layers_and_offsets) {
     ui::Layer* layer = layer_and_offset.first;
-    layer->GetAnimator()->StopAnimating();
     std::unique_ptr<ui::ScopedLayerAnimationSettings> settings;
     if (!callback.is_null()) {
       settings = std::make_unique<ui::ScopedLayerAnimationSettings>(