chrome: Cleanup class/struct forward declarations

chrome/browser/ui/views/tabs/tab_drag_controller.h

 // Copyright (c) 2012 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 CHROME_BROWSER_UI_VIEWS_TABS_TAB_DRAG_CONTROLLER_H_
 #define CHROME_BROWSER_UI_VIEWS_TABS_TAB_DRAG_CONTROLLER_H_
 
 #include <stddef.h>
 
 #include <memory>
 #include <vector>
 
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/message_loop/message_loop.h"
 #include "base/timer/timer.h"
 #include "chrome/browser/ui/tabs/tab_strip_model_observer.h"
 #include "chrome/browser/ui/views/tabs/tab_strip_types.h"
 #include "ui/base/models/list_selection_model.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/views/widget/widget_observer.h"
 
-namespace gfx {
-class Screen;
-}
 namespace ui {
 class EventHandler;
 class ListSelectionModel;
 }
 namespace views {
 class View;
 }
 class Browser;
 class Tab;
 class TabDragControllerTest;
-struct TabRendererData;
 class TabStrip;
 class TabStripModel;
 class WindowFinder;
 
 // TabDragController is responsible for managing the tab dragging session. When
 // the user presses the mouse on a tab a new TabDragController is created and
 // Drag() is invoked as the mouse is dragged. If the mouse is dragged far enough
 // TabDragController starts a drag session. The drag session is completed when
 // EndDrag() is invoked (or the TabDragController is destroyed).
 //
@@ skipping 556 matching lines @@
   std::unique_ptr<ui::EventHandler> escape_tracker_;
 
   std::unique_ptr<WindowFinder> window_finder_;
 
   base::WeakPtrFactory<TabDragController> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(TabDragController);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_TABS_TAB_DRAG_CONTROLLER_H_