Coverity: Fix leaking TransportDIB in GpuBackingStore{GLX,Win}::OnPaintToBackingStore

chrome/gpu/gpu_backing_store_glx.cc

 // Copyright (c) 2010 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 "chrome/gpu/gpu_backing_store_glx.h"
 
 #include "app/gfx/gl/gl_bindings.h"
 #include "app/surface/transport_dib.h"
 #include "base/scoped_ptr.h"
 #include "chrome/common/gpu_messages.h"
@@ skipping 45 matching lines @@
   // FIXME(brettw) does this mean we aren't getting any more messages and we
   // should delete outselves?
   NOTIMPLEMENTED();
 }
 
 void GpuBackingStoreGLX::OnPaintToBackingStore(
     base::ProcessId source_process_id,
     TransportDIB::Id id,
     const gfx::Rect& bitmap_rect,
     const std::vector<gfx::Rect>& copy_rects) {
-  TransportDIB* dib = TransportDIB::Map(id);
+  scoped_ptr<TransportDIB> dib(TransportDIB::Map(id));
   view_->BindContext();
 
   scoped_ptr<skia::PlatformCanvas> canvas(
       dib->GetPlatformCanvas(bitmap_rect.width(), bitmap_rect.height()));
   const SkBitmap& transport_bitmap =
       canvas->getTopPlatformDevice().accessBitmap(false);
 
   for (size_t i = 0; i < copy_rects.size(); i++)
     PaintOneRectToBackingStore(transport_bitmap, bitmap_rect, copy_rects[i]);
 
@@ skipping 143 matching lines @@
     DCHECK(err == GL_NO_ERROR) << "Error " << err <<
            " copying (" << copy_rect.x() << "," << copy_rect.y() <<
            ")," << copy_rect.width() << "x" << copy_rect.height() <<
            " for bitmap " << texture_size_.width() << "x" <<
            texture_size_.height() <<
            " real size " << existing_width << "x" << existing_height <<
            " for " << this;
     */
   }
 }