Add test to verify that the stacking controller picks the correct activatable window for menu.

ui/aura_shell/stacking_controller_unittest.cc

Index: ui/aura_shell/stacking_controller_unittest.cc
diff --git a/ui/aura_shell/stacking_controller_unittest.cc b/ui/aura_shell/stacking_controller_unittest.cc
index cf4fdc7c3a4959180b38a8f865ea94bde78a4cc5..61e0efe0d1915ba1976038468f5469c6a03b3702 100644
--- a/ui/aura_shell/stacking_controller_unittest.cc
+++ b/ui/aura_shell/stacking_controller_unittest.cc
@@ -5,6 +5,7 @@
 #include "ui/aura_shell/stacking_controller.h"
 
 #include "ui/aura/desktop.h"
+#include "ui/aura/test/event_generator.h"
 #include "ui/aura/test/test_windows.h"
 #include "ui/aura/test/test_window_delegate.h"
 #include "ui/aura_shell/test/aura_shell_test_base.h"
@@ -28,5 +29,31 @@ TEST_F(StackingControllerTest, GetTopmostWindowToActivate) {
       GetTopmostWindowToActivate(NULL));
 }
 
+// Test if the clicking on a menu picks the transient parent as activatable
+// window.
+TEST_F(StackingControllerTest, ClickOnMenu) {
+  aura::test::ActivateWindowDelegate activate;
+  aura::test::ActivateWindowDelegate non_activate(false);
+
+  scoped_ptr<aura::Window> w1(aura::test::CreateTestWindowWithDelegate(
+      &activate, 1, gfx::Rect(100, 100), NULL));
+  EXPECT_EQ(NULL, aura::Desktop::GetInstance()->active_window());
+
+  // Clicking on an activatable window activtes the window.
+  aura::test::EventGenerator generator(w1.get());
+  generator.ClickLeftButton();
+  EXPECT_EQ(w1.get(), aura::Desktop::GetInstance()->active_window());
+
+  // Creates a menu that covers the transient parent.
+  scoped_ptr<aura::Window> menu(aura::test::CreateTestWindowWithDelegateAndType(
+      &non_activate, aura::WINDOW_TYPE_MENU, 2, gfx::Rect(100, 100), NULL));
+  w1->AddTransientChild(menu.get());
+
+  // Clicking on a menu whose transient parent is active window shouldn't
+  // change the active window.
+  generator.ClickLeftButton();
+  EXPECT_EQ(w1.get(), aura::Desktop::GetInstance()->active_window());
+}
+
 }  // namespace test
 }  // namespace aura_shell