Fix crash during shutdown

athena/env/athena_env_impl.cc

 // Copyright 2014 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 "athena/env/public/athena_env.h"
 
 #include "athena/util/fill_layout_manager.h"
 #include "base/sys_info.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/client/cursor_client.h"
@@ skipping 16 matching lines @@
 #include "ui/wm/core/native_cursor_manager.h"
 #include "ui/wm/core/native_cursor_manager_delegate.h"
 #include "ui/wm/core/user_activity_detector.h"
 
 namespace athena {
 
 namespace {
 
 AthenaEnv* instance = NULL;
 
+// Screen object used during shutdown.
+gfx::Screen* screen_for_shutdown = NULL;
+
+// TODO(flackr:oshima): Remove this once athena switches to share
+// ash::DisplayManager.
+class ScreenForShutdown : public gfx::Screen {
+ public:
+  // Creates and sets the screen for shutdown. Deletes existing one if any.
+  static void Create(const gfx::Screen* screen) {
+    delete screen_for_shutdown;
+    screen_for_shutdown = new ScreenForShutdown(screen->GetPrimaryDisplay());
+    gfx::Screen::SetScreenInstance(gfx::SCREEN_TYPE_NATIVE,
+                                   screen_for_shutdown);
+  }
+
+ private:
+  explicit ScreenForShutdown(const gfx::Display& primary_display)
+      : primary_display_(primary_display) {}
+
+  // gfx::Screen overrides:
+  virtual bool IsDIPEnabled() OVERRIDE { return true; }
+  virtual gfx::Point GetCursorScreenPoint() OVERRIDE { return gfx::Point(); }
+  virtual gfx::NativeWindow GetWindowUnderCursor() OVERRIDE { return NULL; }
+  virtual gfx::NativeWindow GetWindowAtScreenPoint(
+      const gfx::Point& point) OVERRIDE {
+    return NULL;
+  }
+  virtual int GetNumDisplays() const OVERRIDE { return 1; }
+  virtual std::vector<gfx::Display> GetAllDisplays() const OVERRIDE {
+    std::vector<gfx::Display> displays(1, primary_display_);
+    return displays;
+  }
+  virtual gfx::Display GetDisplayNearestWindow(
+      gfx::NativeView view) const OVERRIDE {
+    return primary_display_;
+  }
+  virtual gfx::Display GetDisplayNearestPoint(
+      const gfx::Point& point) const OVERRIDE {
+    return primary_display_;
+  }
+  virtual gfx::Display GetDisplayMatching(
+      const gfx::Rect& match_rect) const OVERRIDE {
+    return primary_display_;
+  }
+  virtual gfx::Display GetPrimaryDisplay() const OVERRIDE {
+    return primary_display_;
+  }
+  virtual void AddObserver(gfx::DisplayObserver* observer) OVERRIDE {
+    NOTREACHED() << "Observer should not be added during shutdown";
+  }
+  virtual void RemoveObserver(gfx::DisplayObserver* observer) OVERRIDE {}
+
+  const gfx::Display primary_display_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScreenForShutdown);
+};
+
 // A class that bridges the gap between CursorManager and Aura. It borrows
 // heavily from AshNativeCursorManager.
 class AthenaNativeCursorManager : public wm::NativeCursorManager {
  public:
   explicit AthenaNativeCursorManager(aura::WindowTreeHost* host)
       : host_(host), image_cursors_(new ui::ImageCursors) {}
   virtual ~AthenaNativeCursorManager() {}
 
   // wm::NativeCursorManager overrides.
   virtual void SetDisplay(const gfx::Display& display,
@@ skipping 128 matching lines @@
     }
     root_window_event_filter_.reset();
     capture_client_.reset();
     input_method_filter_.reset();
     cursor_manager_.reset();
     user_activity_notifier_.reset();
     user_activity_detector_.reset();
 
     input_method_filter_.reset();
     host_.reset();
+
+    ScreenForShutdown::Create(screen_.get());
     screen_.reset();
-    gfx::Screen::SetScreenInstance(gfx::SCREEN_TYPE_NATIVE, NULL);
-
     aura::Env::DeleteInstance();
 
     display_configurator_->RemoveObserver(this);
     display_configurator_.reset();
   }
 
  private:
   virtual aura::WindowTreeHost* GetHost() OVERRIDE { return host_.get(); }
 
   // AthenaEnv:
@@ skipping 53 matching lines @@
 
 // static
 
 // static
 void AthenaEnv::Shutdown() {
   DCHECK(instance);
   delete instance;
 }
 
 }  // namespace athena