Code: BackendImpl::BackendImpl(
    const base::FilePath& path,
    scoped_refptr<BackendCleanupTracker> cleanup_tracker,
    const scoped_refptr<base::SingleThreadTaskRunner>& cache_thread,
    net::NetLog* net_log)
    : cleanup_tracker_(std::move(cleanup_tracker)),
      background_queue_(this, FallbackToInternalIfNull(cache_thread)),
      path_(path),
      block_files_(path),
      mask_(0),
      max_size_(0),
      up_ticks_(0),
      cache_type_(net::DISK_CACHE),
      uma_report_(0),
      user_flags_(0),
      init_(false),
      restarted_(false),
      unit_test_(false),
      read_only_(false),
      disabled_(false),
       new_eviction_(false),
       first_timer_(true),
       user_load_(false),
       net_log_(net_log),
       done_(base::WaitableEvent::ResetPolicy::MANUAL,
             base::WaitableEvent::InitialState::NOT_SIGNALED),
      ptr_factory_(this) {}

Vulnerability Type: Exec Code 
CWE ID: CWE-20
Summary: Re-entry of a destructor in Networking Disk Cache in Google Chrome prior to 66.0.3359.117 allowed a remote attacker to execute arbitrary code via a crafted HTML page.
Commit Message: Blockfile cache: fix long-standing sparse + evict reentrancy problem

Thanks to nedwilliamson@ (on gmail) for an alternative perspective
plus a reduction to make fixing this much easier.

Bug: 826626, 518908, 537063, 802886
Change-Id: Ibfa01416f9a8e7f7b361e4f93b4b6b134728b85f
Reviewed-on: https://chromium-review.googlesource.com/985052
Reviewed-by: Matt Menke <mmenke@chromium.org>
Commit-Queue: Maks Orlovich <morlovich@chromium.org>
Cr-Commit-Position: refs/heads/master@{#547103}