Add a network quality cache observer

net/nqe/network_quality_store.cc

 // Copyright 2016 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 "net/nqe/network_quality_store.h"
 
 #include "net/base/network_change_notifier.h"
 
 namespace net {
 
@@ skipping 41 matching lines @@
       if ((it->second).OlderThan(oldest_entry_iterator->second))
         oldest_entry_iterator = it;
     }
     cached_network_qualities_.erase(oldest_entry_iterator);
   }
 
   cached_network_qualities_.insert(
       std::make_pair(network_id, cached_network_quality));
   DCHECK_LE(cached_network_qualities_.size(),
             static_cast<size_t>(kMaximumNetworkQualityCacheSize));
+
+  FOR_EACH_OBSERVER(
+      NetworkQualitiesCacheObserver, network_qualities_cache_observer_list_,
+      OnChangeInCachedNetworkQuality(network_id, cached_network_quality));
 }
 
 bool NetworkQualityStore::GetById(
     const nqe::internal::NetworkID& network_id,
     nqe::internal::CachedNetworkQuality* cached_network_quality) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   CachedNetworkQualities::const_iterator it =
       cached_network_qualities_.find(network_id);
 
   if (it == cached_network_qualities_.end())
     return false;
 
   *cached_network_quality = it->second;
   return true;
 }
 
+void NetworkQualityStore::AddNetworkQualitiesCacheObserver(
+    nqe::internal::NetworkQualityStore::NetworkQualitiesCacheObserver*
+        observer) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  network_qualities_cache_observer_list_.AddObserver(observer);
+}
+
+void NetworkQualityStore::RemoveNetworkQualitiesCacheObserver(
+    nqe::internal::NetworkQualityStore::NetworkQualitiesCacheObserver*
+        observer) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  network_qualities_cache_observer_list_.RemoveObserver(observer);
+}
+
 }  // namespace internal
 
 }  // namespace nqe
 
 }  // namespace net