services/ui: Create a proper component for the client-lib.

services/ui/public/cpp/window_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_UI_PUBLIC_CPP_WINDOW_OBSERVER_H_
 #define SERVICES_UI_PUBLIC_CPP_WINDOW_OBSERVER_H_
 
 #include <stdint.h>
 
 #include <vector>
 
+#include "services/ui/public/cpp/ui_export.h"
 #include "services/ui/public/cpp/window.h"
 
 namespace ui {
 
 class Window;
 
 // A note on -ing and -ed suffixes:
 //
 // -ing methods are called before changes are applied to the local window model.
 // -ed methods are called after changes are applied to the local window model.
 //
 // If the change originated from another connection to the window manager, it's
 // possible that the change has already been applied to the service-side model
 // prior to being called, so for example in the case of OnWindowDestroying(),
 // it's possible the window has already been destroyed on the service side.
 
-class WindowObserver {
+class UI_EXPORT WindowObserver {
  public:
-  struct TreeChangeParams {
+  struct UI_EXPORT TreeChangeParams {
     TreeChangeParams();
     Window* target;
     Window* old_parent;
     Window* new_parent;
     Window* receiver;
   };
 
   virtual void OnTreeChanging(const TreeChangeParams& params) {}
   virtual void OnTreeChanged(const TreeChangeParams& params) {}
 
@@ skipping 60 matching lines @@
   // allows the close it should destroy the window as appropriate.
   virtual void OnRequestClose(Window* window) {}
 
  protected:
   virtual ~WindowObserver() {}
 };
 
 }  // namespace ui
 
 #endif  // SERVICES_UI_PUBLIC_CPP_WINDOW_OBSERVER_H_