Overview Desks: Display close button for switch access

Make the close desk button visible and navigable for switch access
users.

Switch access users are unable to execute keyboard commands through
their physical switch devices, rendering them unable to close virtual
spaces without the close buttons being visible.

Test: manual
Change-Id: I8624783a586424307971f0a27ba9c80456fa788b
Fixed: 997011
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2391594
Commit-Queue: Richard Chui <richui@chromium.org>
Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Cr-Commit-Position: refs/heads/master@{#805597}

ash/wm/desks/desk_mini_view.cc

@@ -75,15 +75,13 @@ DeskMiniView::DeskMiniView(DesksBarView* owner_bar,
   SetPaintToLayer();
   layer()->SetFillsBoundsOpaquely(false);
 
-  auto close_desk_button = std::make_unique<CloseDeskButton>(this);
-  close_desk_button->SetVisible(false);
-
   // TODO(afakhry): Tooltips.
 
   desk_preview_ = AddChildView(std::make_unique<DeskPreviewView>(this));
   desk_name_view_ = AddChildView(std::move(desk_name_view));
-  close_desk_button_ = AddChildView(std::move(close_desk_button));
+  close_desk_button_ = AddChildView(std::make_unique<CloseDeskButton>(this));
 
+  UpdateCloseButtonVisibility();
   UpdateBorderColor();
 }
 
@@ -104,13 +102,16 @@ bool DeskMiniView::IsDeskNameBeingModified() const {
   return desk_name_view_->HasFocus();
 }
 
-void DeskMiniView::OnHoverStateMayHaveChanged() {
+void DeskMiniView::UpdateCloseButtonVisibility() {
   // Don't show the close button when hovered while the dragged window is on
   // the DesksBarView.
+  // For switch access, setting the close button to visible allows users to
+  // navigate to it.
   close_desk_button_->SetVisible(
       DesksController::Get()->CanRemoveDesks() &&
       !owner_bar_->dragged_item_over_bar() &&
-      (IsMouseHovered() || force_show_close_button_));
+      (IsMouseHovered() || force_show_close_button_ ||
+       Shell::Get()->accessibility_controller()->IsSwitchAccessRunning()));
 }
 
 void DeskMiniView::OnWidgetGestureTap(const gfx::Rect& screen_rect,
@@ -124,7 +125,7 @@ void DeskMiniView::OnWidgetGestureTap(const gfx::Rect& screen_rect,
       (!is_long_gesture && close_desk_button_->GetVisible() &&
        close_desk_button_->DoesIntersectScreenRect(screen_rect));
   if (old_force_show_close_button != force_show_close_button_)
-    OnHoverStateMayHaveChanged();
+    UpdateCloseButtonVisibility();
 }
 
 void DeskMiniView::UpdateBorderColor() {

ash/wm/desks/desk_mini_view.h

@@ -57,8 +57,8 @@ class ASH_EXPORT DeskMiniView
   bool IsDeskNameBeingModified() const;
 
   // Updates the visibility state of the close button depending on whether this
-  // view is mouse hovered.
-  void OnHoverStateMayHaveChanged();
+  // view is mouse hovered, or if switch access is enabled.
+  void UpdateCloseButtonVisibility();
 
   // Gesture tapping may affect the visibility of the close button. There's only
   // one mini_view that shows the close button on long press at any time.

ash/wm/desks/desks_bar_view.cc

@@ -221,7 +221,7 @@ float DesksBarView::GetOnHoverWindowSizeScaleFactor() const {
 
 void DesksBarView::OnHoverStateMayHaveChanged() {
   for (auto* mini_view : mini_views_)
-    mini_view->OnHoverStateMayHaveChanged();
+    mini_view->UpdateCloseButtonVisibility();
 }
 
 void DesksBarView::OnGestureTap(const gfx::Rect& screen_rect,
@@ -340,15 +340,18 @@ void DesksBarView::OnDeskRemoved(const Desk* desk) {
   const int begin_x = GetFirstMiniViewXOffset();
   // Remove the mini view from the list now. And remove it from its parent
   // after the animation is done.
-  DeskMiniView* mini_view = *iter;
+  DeskMiniView* removed_mini_view = *iter;
   auto partition_iter = mini_views_.erase(iter);
 
   UpdateMinimumWidthToFitContents();
   overview_grid_->OnDesksChanged();
   new_desk_button_->UpdateButtonState();
 
+  for (auto* mini_view : mini_views_)
+    mini_view->UpdateCloseButtonVisibility();
+
   PerformRemoveDeskMiniViewAnimation(
-      mini_view,
+      removed_mini_view,
       std::vector<DeskMiniView*>(mini_views_.begin(), partition_iter),
       std::vector<DeskMiniView*>(partition_iter, mini_views_.end()),
       begin_x - GetFirstMiniViewXOffset());