Fix the bug of multiple overlays.

ash/test/test_overlay_delegate.h

Index: ash/test/test_overlay_delegate.h
diff --git a/ash/test/test_overlay_delegate.h b/ash/test/test_overlay_delegate.h
new file mode 100644
index 0000000000000000000000000000000000000000..d43903fa8427a602b8e326df515c8642fadddc25
--- /dev/null
+++ b/ash/test/test_overlay_delegate.h
@@ -0,0 +1,34 @@
+// Copyright 2014 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.
+
+#ifndef ASH_TEST_TEST_OVERLAY_DELEGATE_H_
+#define ASH_TEST_TEST_OVERLAY_DELEGATE_H_
+
+#include "ash/wm/overlay_event_filter.h"
+
+namespace ash {
+namespace test {
+
+class TestOverlayDelegate : public OverlayEventFilter::Delegate {
+ public:
+  TestOverlayDelegate();
+  virtual ~TestOverlayDelegate();
+
+  int GetCancelCountAndReset();
+
+ private:
+  // Overridden from OverlayEventFilter::Delegate:
+  virtual void Cancel() OVERRIDE;
+  virtual bool IsCancelingKeyEvent(ui::KeyEvent* event) OVERRIDE;
+  virtual aura::Window* GetWindow() OVERRIDE;
+
+  int cancel_count_;
+
+  DISALLOW_COPY_AND_ASSIGN(TestOverlayDelegate);
+};
+
+}  // namespace test
+}  // namespace ash
+
+#endif  // ASH_TEST_TEST_OVERLAY_DELEGATE_H_