Add NULL check in SystemTray::ShowDetailedView.

ash/system/tray/system_tray_unittest.cc

 // Copyright (c) 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/system/tray/system_tray.h"
 
 #include <vector>
 
 #include "ash/root_window_controller.h"
 #include "ash/system/status_area_widget.h"
@@ skipping 71 matching lines @@
   views::View* detailed_view() const { return detailed_view_; }
   views::View* notification_view() const { return notification_view_; }
 
  private:
   views::View* tray_view_;
   views::View* default_view_;
   views::View* detailed_view_;
   views::View* notification_view_;
 };
 
+// Trivial item implementation that returns NULL from tray/default/detailed view
+// creation methods.
+class TestNoViewItem : public SystemTrayItem {
+ public:
+  TestNoViewItem() : SystemTrayItem(GetSystemTray()) {}
+
+  virtual views::View* CreateTrayView(user::LoginStatus status) OVERRIDE {
+    return NULL;
+  }
+
+  virtual views::View* CreateDefaultView(user::LoginStatus status) OVERRIDE {
+    return NULL;
+  }
+
+  virtual views::View* CreateDetailedView(user::LoginStatus status) OVERRIDE {
+    return NULL;
+  }
+
+  virtual views::View* CreateNotificationView(
+      user::LoginStatus status) OVERRIDE {
+    return NULL;
+  }
+
+  virtual void DestroyTrayView() OVERRIDE {}
+  virtual void DestroyDefaultView() OVERRIDE {}
+  virtual void DestroyDetailedView() OVERRIDE {}
+  virtual void DestroyNotificationView() OVERRIDE {}
+  virtual void UpdateAfterLoginStatusChange(user::LoginStatus status) OVERRIDE {
+  }
+};
+
 }  // namespace
 
 typedef AshTestBase SystemTrayTest;
 
 TEST_F(SystemTrayTest, SystemTrayDefaultView) {
   SystemTray* tray = GetSystemTray();
   ASSERT_TRUE(tray->GetWidget());
 
   tray->ShowDefaultView(BUBBLE_CREATE_NEW);
 
@@ skipping 27 matching lines @@
   ASSERT_TRUE(test_item->default_view() == NULL);
   ASSERT_TRUE(detailed_item->detailed_view() != NULL);
 
   // Show the default view, ensure it's created and the detailed view destroyed.
   tray->ShowDefaultView(BUBBLE_CREATE_NEW);
   RunAllPendingInMessageLoop();
   ASSERT_TRUE(test_item->default_view() != NULL);
   ASSERT_TRUE(detailed_item->detailed_view() == NULL);
 }
 
+TEST_F(SystemTrayTest, SystemTrayNoViewItems) {
+  SystemTray* tray = GetSystemTray();
+  ASSERT_TRUE(tray->GetWidget());
+
+  // Verify that no crashes occur on items lacking some views.
+  TestNoViewItem* no_view_item = new TestNoViewItem;
+  tray->AddTrayItem(no_view_item);
+  tray->ShowDefaultView(BUBBLE_CREATE_NEW);
+  tray->ShowDetailedView(no_view_item, 0, false, BUBBLE_USE_EXISTING);
+  RunAllPendingInMessageLoop();
+}
+
 TEST_F(SystemTrayTest, TrayWidgetAutoResizes) {
   SystemTray* tray = GetSystemTray();
   ASSERT_TRUE(tray->GetWidget());
 
   // Add an initial tray item so that the tray gets laid out correctly.
   TestItem* initial_item = new TestItem;
   tray->AddTrayItem(initial_item);
 
   gfx::Size initial_size = tray->GetWidget()->GetWindowBoundsInScreen().size();
 
@@ skipping 80 matching lines @@
   tray->ShowDefaultView(BUBBLE_USE_EXISTING);
   RunAllPendingInMessageLoop();
 
   EXPECT_EQ(bubble_bounds.ToString(), test_item->default_view()->GetWidget()->
       GetWindowBoundsInScreen().ToString());
   EXPECT_EQ(widget, test_item->default_view()->GetWidget());
 }
 
 }  // namespace test
 }  // namespace ash