Fix "modal isn't modal in multi displays" issue

ash/wm/system_modal_container_layout_manager_unittest.cc

Index: ash/wm/system_modal_container_layout_manager_unittest.cc
diff --git a/ash/wm/system_modal_container_layout_manager_unittest.cc b/ash/wm/system_modal_container_layout_manager_unittest.cc
index c1579cff48ca90f923b6b0f40b06053a3eccaabb..4fe89be1737bb5f733bbaba0eea3ecfab68cbd2d 100644
--- a/ash/wm/system_modal_container_layout_manager_unittest.cc
+++ b/ash/wm/system_modal_container_layout_manager_unittest.cc
@@ -4,6 +4,8 @@
 
 #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"
 #include "ash/root_window_controller.h"
@@ -13,6 +15,8 @@
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
 #include "base/run_loop.h"
+#include "ui/aura/client/aura_constants.h"
+#include "ui/aura/test/test_window_delegate.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/compositor/layer.h"
@@ -648,5 +652,56 @@ TEST_F(SystemModalContainerLayoutManagerTest,
   ShowKeyboard(false);
 }
 
+namespace {
+
+class InputTestDelegate : public aura::test::TestWindowDelegate {
+ public:
+  InputTestDelegate() {}
+  ~InputTestDelegate() override {}
+
+  // ui::EventHandler:
+  void OnMouseEvent(ui::MouseEvent* event) override { mouse_event_count_++; }
+
+  int mouse_event_count() const { return mouse_event_count_; }
+
+ private:
+  int mouse_event_count_ = 0;
+
+  DISALLOW_COPY_AND_ASSIGN(InputTestDelegate);
+};
+
+}  // namespace
+
+// Make sure that events are properly blocked in multi displays environment.
+TEST_F(SystemModalContainerLayoutManagerTest, BlockEvent) {
+  UpdateDisplay("500x500, 500x500");
+  InputTestDelegate delegate;
+  std::unique_ptr<aura::Window> window(CreateTestWindowInShellWithDelegate(
+      &delegate, 0, gfx::Rect(0, 0, 100, 100)));
+  window->Show();
+
+  ui::test::EventGenerator e1(Shell::GetPrimaryRootWindow(), window.get());

[James Cook, 2016/06/16 20:31:36]

nit: e1 -> generator, or event_generator, or something longer

[oshima, 2016/06/17 00:06:12]

Done.

+  e1.ClickLeftButton();

[James Cook, 2016/06/16 20:31:36]

optional: Do you need to do this click? It might be clearer just to go to the
"events should be blocked" case and have the mouse_event_count() be 0.

[oshima, 2016/06/17 00:06:12]

I want to make sure I can receive the event first, but I can remove if you want.
let me know.

[James Cook, 2016/06/17 16:04:43]

No, this is fine.

+  EXPECT_EQ(2, delegate.mouse_event_count());
+
+  views::Widget* widget = views::Widget::CreateWindowWithContextAndBounds(
+      new TestWindow(true), Shell::GetPrimaryRootWindow(),
+      gfx::Rect(200, 200, 100, 100));
+  widget->Show();
+  EXPECT_TRUE(Shell::GetInstance()->IsSystemModalWindowOpen());
+
+  // Events should be blocked.
+  e1.ClickLeftButton();
+  EXPECT_EQ(2, delegate.mouse_event_count());
+  widget->Close();
+
+  EXPECT_FALSE(Shell::GetInstance()->IsSystemModalWindowOpen());
+  e1.ClickLeftButton();
+  EXPECT_EQ(4, delegate.mouse_event_count());
+
+  // We need to delete window here because delegate is on the stack.
+  window.reset();
+}
+
 }  // namespace test
 }  // namespace ash