Code:  void WallpaperManager::OnDefaultWallpaperDecoded(
     const base::FilePath& path,
     const wallpaper::WallpaperLayout layout,
     std::unique_ptr<user_manager::UserImage>* result_out,
     MovableOnDestroyCallbackHolder on_finish,
     std::unique_ptr<user_manager::UserImage> user_image) {
  if (user_image->image().isNull()) {
    LOG(ERROR) << "Failed to decode default wallpaper. ";
    return;
   }
 
   *result_out = std::move(user_image);
  WallpaperInfo info(path.value(), layout, wallpaper::DEFAULT,
                     base::Time::Now().LocalMidnight());
  SetWallpaper((*result_out)->image(), info);
 }

Vulnerability Type: XSS +Info 
CWE ID: CWE-200
Summary: The XSSAuditor::canonicalize function in core/html/parser/XSSAuditor.cpp in the XSS auditor in Blink, as used in Google Chrome before 44.0.2403.89, does not properly choose a truncation point, which makes it easier for remote attackers to obtain sensitive information via an unspecified linear-time attack.
Commit Message: [reland] Do not set default wallpaper unless it should do so.

TBR=bshe@chromium.org, alemate@chromium.org

Bug: 751382
Change-Id: Id0793dfe467f737526a95b1e66ed01fbb8860bda
Reviewed-on: https://chromium-review.googlesource.com/619754
Commit-Queue: Xiaoqian Dai <xdai@chromium.org>
Reviewed-by: Alexander Alekseev <alemate@chromium.org>
Reviewed-by: Biao She <bshe@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#498325}
Reviewed-on: https://chromium-review.googlesource.com/646430
Cr-Commit-Position: refs/heads/master@{#498982}