Delete activity upon window deletion

athena/activity/activity_manager_impl.h

Index: athena/activity/activity_manager_impl.h
diff --git a/athena/activity/activity_manager_impl.h b/athena/activity/activity_manager_impl.h
new file mode 100644
index 0000000000000000000000000000000000000000..2a109fd670cb4533fbfa33018829e623b954cbfc
--- /dev/null
+++ b/athena/activity/activity_manager_impl.h
@@ -0,0 +1,31 @@
+// 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.
+
+#include "athena/activity/public/activity_manager.h"
+
+#include <vector>
+
+#include "base/macros.h"
+
+namespace athena {
+
+class ActivityManagerImpl : public ActivityManager {
+ public:
+  ActivityManagerImpl();
+  virtual ~ActivityManagerImpl();
+
+  int num_activities() const { return activities_.size(); }
+
+  // ActivityManager:
+  virtual void AddActivity(Activity* activity) OVERRIDE;
+  virtual void RemoveActivity(Activity* activity) OVERRIDE;
+  virtual void UpdateActivity(Activity* activity) OVERRIDE;
+
+ private:
+  std::vector<Activity*> activities_;
+
+  DISALLOW_COPY_AND_ASSIGN(ActivityManagerImpl);
+};
+
+}  // namespace athena