Fix memory leak in GetBookmarkFolderIcon.

Change-Id: Ia38e827130b7cbb553a3954c5b5df58f506a7e70
Reviewed-on: https://chromium-review.googlesource.com/1136515Reviewed-by: Elly Fong-Jones <ellyjones@chromium.org>
Commit-Queue: Erik Chen <erikchen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#574967}

chrome/browser/ui/bookmarks/bookmark_utils.cc

@@ -301,9 +301,10 @@ gfx::ImageSkia GetBookmarkFolderIcon(SkColor text_color) {
   int resource_id = color_utils::IsDark(text_color)
                         ? IDR_BOOKMARK_BAR_FOLDER
                         : IDR_BOOKMARK_BAR_FOLDER_WHITE;
-  return *ui::ResourceBundle::GetSharedInstance()
-              .GetNativeImageNamed(resource_id)
-              .CopyImageSkia();
+  std::unique_ptr<gfx::ImageSkia> image(ui::ResourceBundle::GetSharedInstance()
+                                            .GetNativeImageNamed(resource_id)
+                                            .CopyImageSkia());
+  return *image.get();
 #else
   return GetFolderIcon(ui::MaterialDesignController::IsTouchOptimizedUiEnabled()
                            ? vector_icons::kFolderTouchIcon