Connect BackgroundFetch to the OfflineItemCollection

components/offline_items_collection/core/offline_content_aggregator.cc

 // Copyright 2017 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 <algorithm>
 #include <string>
 #include <utility>
 
 #include "base/bind.h"
 #include "base/memory/ptr_util.h"
@@ skipping 33 matching lines @@
   // with any other namespace.
   if (!MapContainsValue(providers_, provider))
     provider->AddObserver(this);
 
   providers_[name_space] = provider;
 }
 
 void OfflineContentAggregator::UnregisterProvider(
     const std::string& name_space) {
   auto provider_it = providers_.find(name_space);
+  if (provider_it == providers_.end())

[David Trainor- moved to gerrit, 2017/04/19 22:45:12]

Ty!

+    return;
 
   OfflineContentProvider* provider = provider_it->second;
   providers_.erase(provider_it);
 
   // Only clean up the connection to the provider if the provider isn't
   // associated with any other namespace.
   if (!MapContainsValue(providers_, provider)) {
     provider->RemoveObserver(this);
     pending_actions_.erase(provider);
   }
@@ skipping 204 matching lines @@
 
 void OfflineContentAggregator::RunIfReady(OfflineContentProvider* provider,
                                           const base::Closure& action) {
   if (provider->AreItemsAvailable())
     action.Run();
   else
     pending_actions_[provider].push_back(action);
 }
 
 }  // namespace offline_items_collection