ozone: dri: Fix undefined references in DRI platform GN build

ui/ozone/platform/dri/dri_window_delegate_manager.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 UI_OZONE_PLATFORM_DRI_DRI_WINDOW_DELEGATE_MANAGER_H_
 #define UI_OZONE_PLATFORM_DRI_DRI_WINDOW_DELEGATE_MANAGER_H_
 
 #include "base/containers/scoped_ptr_hash_map.h"
 #include "ui/gfx/native_widget_types.h"
+#include "ui/ozone/ozone_export.h"
 
 namespace ui {
 
 class DriWindowDelegate;
 
-class DriWindowDelegateManager {
+class OZONE_EXPORT DriWindowDelegateManager {
  public:
   DriWindowDelegateManager();
   ~DriWindowDelegateManager();
 
   // Adds a delegate for |widget|. Note: |widget| should not be associated with
   // a delegate when calling this function.
   void AddWindowDelegate(gfx::AcceleratedWidget widget,
                          scoped_ptr<DriWindowDelegate> surface);
 
   // Removes the delegate for |widget|. Note: |widget| must have a delegate
@@ skipping 10 matching lines @@
       WidgetToDelegateMap;
 
   WidgetToDelegateMap delegate_map_;
 
   DISALLOW_COPY_AND_ASSIGN(DriWindowDelegateManager);
 };
 
 }  // namespace ui
 
 #endif  // UI_OZONE_PLATFORM_DRI_DRI_WINDOW_DELEGATE_MANAGER_H_