Make system modal check more strict

ash/wm/system_modal_container_layout_manager_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/wm/system_modal_container_layout_manager.h"
 
 #include <memory>
 
 #include "ash/common/session/session_state_delegate.h"
 #include "ash/common/shell_window_ids.h"
@@ skipping 658 matching lines @@
   window->SetProperty(aura::client::kModalKey, ui::MODAL_TYPE_NONE);
   EXPECT_FALSE(WmShell::Get()->IsSystemModalWindowOpen());
 
   window->SetProperty(aura::client::kModalKey, ui::MODAL_TYPE_SYSTEM);
   EXPECT_TRUE(WmShell::Get()->IsSystemModalWindowOpen());
 
   widget->Close();
   EXPECT_FALSE(WmShell::Get()->IsSystemModalWindowOpen());
 }
 
+TEST_F(SystemModalContainerLayoutManagerTest, VisibilityChange) {
+  // Create a modal window.
+  std::unique_ptr<aura::Window> parent(OpenToplevelTestWindow(false));
+  std::unique_ptr<aura::Window> modal_window(
+      OpenTestWindowWithParent(parent.get(), true));
+  parent->Show();
+  modal_window->Show();

[James Cook, 2016/06/27 00:33:43]

optional: Maybe test it prior to modal_window->Show() to exercise
OnWindowAddedToLayout()?

[oshima, 2016/06/27 02:26:07]

Done. (turns out the function was calling show, so I create using view::Widget
API instead)

+  EXPECT_TRUE(WmShell::Get()->IsSystemModalWindowOpen());
+  EXPECT_TRUE(Shell::GetPrimaryRootWindowController()

[James Cook, 2016/06/27 00:33:43]

optional nit: Cache pointer to SystemModalLayoutManager?

[oshima, 2016/06/27 02:26:07]

Done.

+                  ->GetSystemModalLayoutManager(modal_window.get())
+                  ->has_modal_background());
+
+  modal_window->Hide();
+  EXPECT_FALSE(WmShell::Get()->IsSystemModalWindowOpen());
+  EXPECT_FALSE(Shell::GetPrimaryRootWindowController()
+                   ->GetSystemModalLayoutManager(modal_window.get())
+                   ->has_modal_background());
+
+  modal_window->Show();
+  EXPECT_TRUE(WmShell::Get()->IsSystemModalWindowOpen());
+  EXPECT_TRUE(Shell::GetPrimaryRootWindowController()
+                  ->GetSystemModalLayoutManager(modal_window.get())
+                  ->has_modal_background());
+}
+
 namespace {
 
 class InputTestDelegate : public aura::test::TestWindowDelegate {
  public:
   InputTestDelegate() {}
   ~InputTestDelegate() override {}
 
   void RunTest(test::AshTestBase* test_base) {
     std::unique_ptr<aura::Window> window(
         test_base->CreateTestWindowInShellWithDelegate(
@@ skipping 81 matching lines @@
   if (!SupportsMultipleDisplays())
     return;
 
   UpdateDisplay("500x500, 500x500");
   InputTestDelegate delegate;
   delegate.RunTest(this);
 }
 
 }  // namespace test
 }  // namespace ash