Add the method to check if offline archive is in internal dir

Bug: 758690
Change-Id: I8bb4283fc40a87fa7a87df2c7e513e2e16903290
Reviewed-on: https://chromium-review.googlesource.com/828049
Reviewed-by: Filip Gorski <fgorski@chromium.org>
Commit-Queue: Jian Li <jianli@chromium.org>
Cr-Commit-Position: refs/heads/master@{#524232}
void OfflinePageModelImpl::FinalizeModelLoad() {
  is_loaded_ = true;


  UMA_HISTOGRAM_BOOLEAN("OfflinePages.Model.FinalLoadSuccessful",
                        store_->state() == StoreState::LOADED);

  for (Observer& observer : observers_)
    observer.OfflinePageModelLoaded(this);

  for (const auto& delayed_task : delayed_tasks_)
    delayed_task.Run();
  delayed_tasks_.clear();

  PostClearStorageIfNeededTask(true /* delayed */);
}

void OfflinePageModelImpl::FinalizeModelLoad() {
  is_loaded_ = true;


  UMA_HISTOGRAM_BOOLEAN("OfflinePages.Model.FinalLoadSuccessful",
                        store_->state() == StoreState::LOADED);

  for (Observer& observer : observers_)
    observer.OfflinePageModelLoaded(this);

  for (const auto& delayed_task : delayed_tasks_)
    delayed_task.Run();
  delayed_tasks_.clear();

  PostClearStorageIfNeededTask(true /* delayed */);
}
