ARC Overlays: Ensure overlay is closed

The overlay window should be closed if the host window is closed, or if
the controller is destroyed.

BUG=crbug:1156540
TEST=Close Test app while overlay is displayed

Change-Id: I7d0dadc697535694952bc9be02c88d4c7a28977a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2582816
Commit-Queue: Lloyd Pique <lpique@chromium.org>
Reviewed-by: Mitsuru Oshima <oshima@chromium.org>
Cr-Commit-Position: refs/heads/master@{#835791}

ash/public/cpp/external_arc/overlay/arc_overlay_controller_impl.cc

@@ -29,7 +29,9 @@ ArcOverlayControllerImpl::ArcOverlayControllerImpl(aura::Window* host_window)
   widget->GetContentsView()->AddChildView(overlay_container_);
 }
 
-ArcOverlayControllerImpl::~ArcOverlayControllerImpl() = default;
+ArcOverlayControllerImpl::~ArcOverlayControllerImpl() {
+  EnsureOverlayWindowClosed();
+}
 
 void ArcOverlayControllerImpl::AttachOverlay(aura::Window* overlay_window) {
   if (!overlay_container_ || !host_window_)
@@ -56,6 +58,8 @@ void ArcOverlayControllerImpl::OnWindowDestroying(aura::Window* window) {
   if (host_window_observer_.IsObservingSource(window)) {
     host_window_ = nullptr;
     host_window_observer_.Reset();
+
+    EnsureOverlayWindowClosed();
   }
   if (overlay_window_observer_.IsObservingSource(window)) {
     overlay_window_ = nullptr;
@@ -101,4 +105,14 @@ void ArcOverlayControllerImpl::ConvertPointFromWindow(aura::Window* window,
   views::View::ConvertPointFromWidget(widget->GetContentsView(), point);
 }
 
+void ArcOverlayControllerImpl::EnsureOverlayWindowClosed() {
+  // Ensure the overlay window is closed.
+  if (overlay_window_observer_.IsObserving()) {
+    VLOG(1) << "Forcing-closing overlay " << overlay_window_->GetName();
+    auto* const widget =
+        views::Widget::GetWidgetForNativeWindow(overlay_window_);
+    widget->CloseWithReason(views::Widget::ClosedReason::kUnspecified);
+  }
+}
+
 }  // namespace ash

ash/public/cpp/external_arc/overlay/arc_overlay_controller_impl.h

@@ -51,6 +51,7 @@ class ASH_PUBLIC_EXPORT ArcOverlayControllerImpl : public ArcOverlayController,
  private:
   void UpdateHostBounds();
   void ConvertPointFromWindow(aura::Window* window, gfx::Point* point);
+  void EnsureOverlayWindowClosed();
 
   aura::Window* host_window_ = nullptr;
   base::ScopedObservation<aura::Window, aura::WindowObserver>