Remove unneeded IconLoader::image_

chrome/browser/icon_loader_auralinux.cc

 // Copyright 2013 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/browser/icon_loader.h"
 
 #include "base/bind.h"
+#include "base/memory/ptr_util.h"
 #include "base/message_loop/message_loop.h"
 #include "base/nix/mime_util_xdg.h"
 #include "ui/views/linux_ui/linux_ui.h"
 
 // static
 IconLoader::IconGroup IconLoader::GroupForFilepath(
     const base::FilePath& file_path) {
   return base::nix::GetFileMimeType(file_path);
 }
 
@@ skipping 13 matching lines @@
     case IconLoader::NORMAL:
       size_pixels = 32;
       break;
     case IconLoader::LARGE:
       size_pixels = 48;
       break;
     default:
       NOTREACHED();
   }
 
+  std::unique_ptr<gfx::Image> image;
   views::LinuxUI* ui = views::LinuxUI::instance();
   if (ui) {
-    gfx::Image image = ui->GetIconForContentType(group_, size_pixels);
-    if (!image.IsEmpty())
-      image_.reset(new gfx::Image(image));
+    image = base::MakeUnique<gfx::Image>(
+        ui->GetIconForContentType(group_, size_pixels));
+    if (image->IsEmpty())
+      image = nullptr;
   }
 
   target_task_runner_->PostTask(
-      FROM_HERE, base::Bind(callback_, base::Passed(&image_), group_));
+      FROM_HERE, base::Bind(callback_, base::Passed(&image), group_));
   delete this;
 }