ui: Cleanup class/struct forward declarations

ui/ozone/platform/drm/gpu/hardware_display_plane.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_DRM_GPU_HARDWARE_DISPLAY_PLANE_H_
 #define UI_OZONE_PLATFORM_DRM_GPU_HARDWARE_DISPLAY_PLANE_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <vector>
 
 #include "base/macros.h"
 #include "ui/ozone/platform/drm/common/scoped_drm_types.h"
 
-namespace gfx {
-class Rect;
-}
-
 namespace ui {
 
 class DrmDevice;
 
 class HardwareDisplayPlane {
  public:
   enum Type { kDummy, kPrimary, kOverlay, kCursor };
 
   HardwareDisplayPlane(uint32_t plane_id, uint32_t possible_crtcs);
 
@@ skipping 32 matching lines @@
   bool in_use_ = false;
   Type type_ = kPrimary;
   std::vector<uint32_t> supported_formats_;
 
   DISALLOW_COPY_AND_ASSIGN(HardwareDisplayPlane);
 };
 
 }  // namespace ui
 
 #endif  // UI_OZONE_PLATFORM_DRM_GPU_HARDWARE_DISPLAY_PLANE_H_