Do not allow system modal dialogs below the lock layer to steal focus.

BUG=110920
TEST=Open a system modal dialog, lock the screen, and verify that you can now unlock the screen.

Review URL: https://chromiumcodereview.appspot.com/9271062

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@119499 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 75 insertions, 0 deletions

diff --git a/ash/wm/system_modal_container_layout_manager.cc b/ash/wm/system_modal_container_layout_manager.cc
index 01a7bfb..3fc56b3 100644
--- a/ash/wm/system_modal_container_layout_manager.cc
+++ b/ash/wm/system_modal_container_layout_manager.cc
@@ -6,6 +6,7 @@
 
 #include "ash/ash_switches.h"
 #include "ash/shell.h"
+#include "ash/shell_window_ids.h"
 #include "ash/wm/system_modal_container_event_filter.h"
 #include "ash/wm/window_animations.h"
 #include "ash/wm/window_util.h"
@@ -143,6 +144,11 @@ void SystemModalContainerLayoutManager::OnLayerAnimationScheduled(
 
 bool SystemModalContainerLayoutManager::CanWindowReceiveEvents(
     aura::Window* window) {
+  // This container can not handle events if the screen is locked and it is not
+  // above the lock screen layer (crbug.com/110920).
+  if (ash::Shell::GetInstance()->IsScreenLocked() &&
+      container_->id() < ash::internal::kShellWindowId_LockScreenContainer)
+    return true;
   return GetActivatableWindow(window) == modal_window();
 }
 
diff --git a/ash/wm/system_modal_container_layout_manager_unittest.cc b/ash/wm/system_modal_container_layout_manager_unittest.cc
index db1fbc5..04198ea 100644
--- a/ash/wm/system_modal_container_layout_manager_unittest.cc
+++ b/ash/wm/system_modal_container_layout_manager_unittest.cc
@@ -12,6 +12,7 @@
 #include "ui/aura/root_window.h"
 #include "ui/aura/test/event_generator.h"
 #include "ui/aura/window.h"
+#include "ui/views/events/event.h"
 #include "ui/views/widget/widget.h"
 #include "ui/views/widget/widget_delegate.h"
 
@@ -62,6 +63,32 @@ class TestWindow : public views::WidgetDelegateView {
   DISALLOW_COPY_AND_ASSIGN(TestWindow);
 };
 
+class EventTestWindow : public TestWindow {
+ public:
+  explicit EventTestWindow(bool modal) : TestWindow(modal),
+                                         mouse_presses_(0) {}
+  virtual ~EventTestWindow() {}
+
+  aura::Window* OpenTestWindow(aura::Window* parent) {
+    views::Widget* widget =
+        views::Widget::CreateWindowWithParent(this, parent);
+    widget->Show();
+    return widget->GetNativeView();
+  }
+
+  // Overridden from views::View:
+  virtual bool OnMousePressed(const views::MouseEvent& event) OVERRIDE {
+    mouse_presses_++;
+    return false;
+  }
+
+  int mouse_presses() const { return mouse_presses_; }
+ private:
+  int mouse_presses_;
+
+  DISALLOW_COPY_AND_ASSIGN(EventTestWindow);
+};
+
 class TransientWindowObserver : public aura::WindowObserver {
  public:
   TransientWindowObserver() : destroyed_(false) {}
@@ -173,5 +200,47 @@ TEST_F(SystemModalContainerLayoutManagerTest,
   EXPECT_TRUE(IsActiveWindow(unrelated.get()));
 }
 
+TEST_F(SystemModalContainerLayoutManagerTest,
+       EventFocusContainers) {
+  // Create a normal window and attempt to receive a click event.
+  EventTestWindow* main_delegate = new EventTestWindow(false);
+  scoped_ptr<aura::Window> main(main_delegate->OpenTestWindow(NULL));
+  EXPECT_TRUE(IsActiveWindow(main.get()));
+  aura::test::EventGenerator e1(main.get());
+  e1.ClickLeftButton();
+  EXPECT_EQ(1, main_delegate->mouse_presses());
+
+  // Create a modal window for the main window and verify that the main window
+  // no longer receives mouse events.
+  EventTestWindow* transient_delegate = new EventTestWindow(true);
+  aura::Window* transient = transient_delegate->OpenTestWindow(main.get());
+  EXPECT_TRUE(IsActiveWindow(transient));
+  e1.ClickLeftButton();
+  EXPECT_EQ(1, transient_delegate->mouse_presses());
+
+  // Create a window in the lock screen container and ensure that it receives
+  // the mouse event instead of the modal window (crbug.com/110920).
+  EventTestWindow* lock_delegate = new EventTestWindow(false);
+  scoped_ptr<aura::Window> lock(lock_delegate->OpenTestWindow(
+      Shell::GetInstance()->GetContainer(
+          ash::internal::kShellWindowId_LockScreenContainer)));
+  EXPECT_TRUE(IsActiveWindow(lock.get()));
+  e1.ClickLeftButton();
+  EXPECT_EQ(1, lock_delegate->mouse_presses());
+
+  // Make sure that a modal container created by the lock screen can still
+  // receive mouse events.
+  EventTestWindow* lock_modal_delegate = new EventTestWindow(true);
+  aura::Window* lock_modal = lock_modal_delegate->OpenTestWindow(lock.get());
+  EXPECT_TRUE(IsActiveWindow(lock_modal));
+  e1.ClickLeftButton();
+  EXPECT_EQ(1, main_delegate->mouse_presses());
+
+  // Verify that none of the other containers received any more mouse presses.
+  EXPECT_EQ(1, transient_delegate->mouse_presses());
+  EXPECT_EQ(1, lock_delegate->mouse_presses());
+  EXPECT_EQ(1, lock_modal_delegate->mouse_presses());
+}
+
 }  // namespace test
 }  // namespace ash