Adds capture to the mojo window_manager.

services/window_manager/capture_controller_observer.h

+// 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 SERVICES_WINDOW_MANAGER_CAPTURE_CONTROLLER_OBSERVER_H_
+#define SERVICES_WINDOW_MANAGER_CAPTURE_CONTROLLER_OBSERVER_H_
+
+namespace window_manager {
+
+class CaptureControllerObserver {
+ public:
+  virtual void OnCaptureChanged(mojo::View* gained_capture,
+                                mojo::View* lost_capture) = 0;
+
+ protected:
+  virtual ~CaptureControllerObserver() {}
+};
+
+}  // namespace window_manager
+
+#endif // SERVICES_WINDOW_MANAGER_CAPTURE_CONTROLLER_OBSERVER_H_