Fixes clang warning in GLSurfaceOzone.

ui/gl/gl_surface_ozone.cc

 // 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.
 
 #include "ui/gl/gl_surface.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/memory/ref_counted.h"
 #include "ui/gfx/native_widget_types.h"
@@ skipping 287 matching lines @@
     bool ScheduleOverlayPlane(gfx::AcceleratedWidget widget,
                               int z_order,
                               gfx::OverlayTransform transform,
                               const gfx::Rect& bounds_rect,
                               const gfx::RectF& crop_rect) override {
       return ui::SurfaceFactoryOzone::GetInstance()->ScheduleOverlayPlane(
           widget, z_order, transform, pixmap_, bounds_rect, crop_rect);
     }
 
    private:
+    ~SurfaceImage() override {}
+
     scoped_refptr<ui::NativePixmap> pixmap_;
   };
 
   ~GLSurfaceOzoneSurfacelessSurfaceImpl() override {
     DCHECK(!fbo_);
     for (size_t i = 0; i < arraysize(textures_); i++)
       DCHECK(!textures_[i]) << "texture " << i << " not released";
   }
 
   void BindFramebuffer() {
@@ skipping 142 matching lines @@
       NOTREACHED();
       return NULL;
   }
 }
 
 EGLNativeDisplayType GetPlatformDefaultEGLNativeDisplay() {
   return ui::SurfaceFactoryOzone::GetInstance()->GetNativeDisplay();
 }
 
 }  // namespace gfx