Fix the bug of multiple overlays.

ash/wm/partial_screenshot_view_unittest.cc

Index: ash/wm/partial_screenshot_view_unittest.cc
diff --git a/ash/wm/partial_screenshot_view_unittest.cc b/ash/wm/partial_screenshot_view_unittest.cc
index 3b763b42ff5045760a0dc723a2e1dabf67708da5..26e27e3ca8bc192d76b3d83963e22bc5b76e6b8a 100644
--- a/ash/wm/partial_screenshot_view_unittest.cc
+++ b/ash/wm/partial_screenshot_view_unittest.cc
@@ -8,33 +8,51 @@
 #include "ash/shell.h"
 #include "ash/shell_window_ids.h"
 #include "ash/test/ash_test_base.h"
+#include "ash/test/test_overlay_delegate.h"
 #include "ash/test/test_screenshot_delegate.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/events/test/event_generator.h"
+#include "ui/views/widget/widget.h"
+#include "ui/views/widget/widget_observer.h"
 
 namespace ash {
 
-class PartialScreenshotViewTest : public test::AshTestBase {
+class PartialScreenshotViewTest : public test::AshTestBase,
+                                  public views::WidgetObserver {
  public:
   PartialScreenshotViewTest() : view_(NULL) {}
-  virtual ~PartialScreenshotViewTest() {}
+  virtual ~PartialScreenshotViewTest() {
+    if (view_)
+      view_->GetWidget()->RemoveObserver(this);
+  }
 
-  virtual void SetUp() OVERRIDE {
-    test::AshTestBase::SetUp();
+  void StartPartialScreenshot() {
     std::vector<PartialScreenshotView*> views =
         PartialScreenshotView::StartPartialScreenshot(GetScreenshotDelegate());
-    ASSERT_EQ(1u, views.size());
-    view_ = views[0];
+    if (!views.empty()) {
+      view_ = views[0];
+      view_->GetWidget()->AddObserver(this);
+    }
   }
 
  protected:
   PartialScreenshotView* view_;
 
  private:
+  // views::WidgetObserver:
+  virtual void OnWidgetDestroying(views::Widget* widget) OVERRIDE {
+    if (view_ && view_->GetWidget() == widget)
+      view_ = NULL;
+    widget->RemoveObserver(this);
+  }
+
   DISALLOW_COPY_AND_ASSIGN(PartialScreenshotViewTest);
 };
 
 TEST_F(PartialScreenshotViewTest, BasicMouse) {
+  StartPartialScreenshot();
+  ASSERT_TRUE(view_);
+
   ui::test::EventGenerator generator(Shell::GetPrimaryRootWindow());
 
   generator.MoveMouseTo(100, 100);
@@ -53,6 +71,9 @@ TEST_F(PartialScreenshotViewTest, BasicMouse) {
 }
 
 TEST_F(PartialScreenshotViewTest, BasicTouch) {
+  StartPartialScreenshot();
+  ASSERT_TRUE(view_);
+
   ui::test::EventGenerator generator(Shell::GetPrimaryRootWindow());
 
   generator.set_current_location(gfx::Point(100,100));
@@ -74,4 +95,28 @@ TEST_F(PartialScreenshotViewTest, BasicTouch) {
   EXPECT_EQ("100,100 100x100", GetScreenshotDelegate()->last_rect().ToString());
 }
 
+// Partial screenshot session should not start when there is already another
+// overlay. See: http://crbug.com/341958
+TEST_F(PartialScreenshotViewTest, DontStartOverOverlay) {
+  OverlayEventFilter* overlay_filter = Shell::GetInstance()->overlay_filter();
+  test::TestOverlayDelegate delegate;
+  overlay_filter->Activate(&delegate);
+  EXPECT_EQ(&delegate, overlay_filter->delegate_);
+
+  StartPartialScreenshot();
+  EXPECT_TRUE(view_ == NULL);
+  EXPECT_EQ(&delegate, overlay_filter->delegate_);
+  overlay_filter->Deactivate(&delegate);
+
+  StartPartialScreenshot();
+  EXPECT_TRUE(view_ != NULL);
+
+  // Someone else attempts to activate the overlay session, which should cancel
+  // the current partial screenshot session.
+  overlay_filter->Activate(&delegate);
+  RunAllPendingInMessageLoop();
+  EXPECT_EQ(&delegate, overlay_filter->delegate_);
+  EXPECT_TRUE(view_ == NULL);
+}
+
 }  // namespace ash