ash: Reorder shutdown of ShelfLayoutManager and StatusAreaWidget

ash/shelf/shelf_widget.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ash/shelf/shelf_widget.h"
 
 #include "ash/ash_switches.h"
 #include "ash/focus_cycler.h"
 #include "ash/root_window_controller.h"
 #include "ash/session/session_state_delegate.h"
@@ skipping 247 matching lines @@
   gfx::Insets GetInsetsForAlignment(int distance,
                                     wm::ShelfAlignment alignment) {
     if (alignment == wm::SHELF_ALIGNMENT_LEFT)
       return gfx::Insets(0, 0, 0, distance);
     if (alignment == wm::SHELF_ALIGNMENT_RIGHT)
       return gfx::Insets(0, distance, 0, 0);
     return gfx::Insets(distance, 0, 0, 0);
   }
 
   // ShelfLayoutManagerObserver:
-  void WillDeleteShelf() override {
+  void WillDeleteShelfLayoutManager() override {
     shelf_->RemoveObserver(this);
     shelf_ = NULL;
   }
 
   void WillChangeVisibilityState(ShelfVisibilityState new_state) override {
     gfx::Insets mouse_insets;
     gfx::Insets touch_insets;
     if (new_state == SHELF_VISIBLE) {
       // Let clicks at the very top of the shelf through so windows can be
       // resized with the bottom-right corner and bottom edge.
@@ skipping 317 matching lines @@
 
   shelf_container->SetEventTargeter(std::unique_ptr<ui::EventTargeter>(
       new ShelfWindowTargeter(shelf_container, shelf_layout_manager_)));
   status_container->SetEventTargeter(std::unique_ptr<ui::EventTargeter>(
       new ShelfWindowTargeter(status_container, shelf_layout_manager_)));
 
   views::Widget::AddObserver(this);
 }
 
 ShelfWidget::~ShelfWidget() {
+  // Must call Shutdown() before destruction.
+  DCHECK(!status_area_widget_);
   Shell::GetInstance()->focus_cycler()->RemoveWidget(this);
   SetFocusCycler(nullptr);
   RemoveObserver(this);
 }
 
 void ShelfWidget::SetPaintsBackground(
     wm::ShelfBackgroundType background_type,
     BackgroundAnimatorChangeType change_type) {
   ui::Layer* opaque_background = delegate_view_->opaque_background();
   float target_opacity =
@@ skipping 128 matching lines @@
 void ShelfWidget::SetFocusCycler(FocusCycler* focus_cycler) {
   delegate_view_->set_focus_cycler(focus_cycler);
   if (focus_cycler)
     focus_cycler->AddWidget(this);
 }
 
 FocusCycler* ShelfWidget::GetFocusCycler() {
   return delegate_view_->focus_cycler();
 }
 
-void ShelfWidget::ShutdownStatusAreaWidget() {
+void ShelfWidget::Shutdown() {
+  // Shutting down the status area widget may cause some widgets (e.g. bubbles)
+  // to close, so uninstall the ShelfLayoutManager event filters first. Don't
+  // reset the pointer until later because other widgets (e.g. app list) may
+  // access it later in shutdown.
+  if (shelf_layout_manager_)
+    shelf_layout_manager_->PrepareForShutdown();
+
   if (status_area_widget_) {
     Shell::GetInstance()->focus_cycler()->RemoveWidget(status_area_widget_);
     status_area_widget_->Shutdown();
+    status_area_widget_ = nullptr;
   }
-  status_area_widget_ = NULL;
 }
 
 void ShelfWidget::ForceUndimming(bool force) {
   delegate_view_->ForceUndimming(force);
 }
 
 void ShelfWidget::OnWidgetActivationChanged(views::Widget* widget,
                                             bool active) {
   activating_as_fallback_ = false;
   if (active)
@@ skipping 12 matching lines @@
   if (delegate_view_)
     return delegate_view_->GetDimmerBoundsForTest();
   return gfx::Rect();
 }
 
 void ShelfWidget::DisableDimmingAnimationsForTest() {
   DCHECK(delegate_view_);
   return delegate_view_->disable_dimming_animations_for_test();
 }
 
-void ShelfWidget::WillDeleteShelf() {
+void ShelfWidget::WillDeleteShelfLayoutManager() {
   shelf_layout_manager_->RemoveObserver(this);
   shelf_layout_manager_ = NULL;
 }
 
 }  // namespace ash