NQE: Notify observer as soon as it is added

net/nqe/network_quality_estimator.cc

 // Copyright 2015 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_estimator.h"
 
 #include <algorithm>
 #include <cmath>
 #include <limits>
 #include <utility>
@@ skipping 1129 matching lines @@
     }
   }
   // Return the fastest connection type.
   return static_cast<EffectiveConnectionType>(EFFECTIVE_CONNECTION_TYPE_LAST -
                                               1);
 }
 
 void NetworkQualityEstimator::AddEffectiveConnectionTypeObserver(
     EffectiveConnectionTypeObserver* observer) {
   DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(observer);
   effective_connection_type_observer_list_.AddObserver(observer);
+
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE, base::Bind(&NetworkQualityEstimator::
+                                NotifyEffectiveConnectionTypeObserverIfPresent,
+                            weak_ptr_factory_.GetWeakPtr(), observer));
 }
 
 void NetworkQualityEstimator::RemoveEffectiveConnectionTypeObserver(
     EffectiveConnectionTypeObserver* observer) {
   DCHECK(thread_checker_.CalledOnValidThread());
   effective_connection_type_observer_list_.RemoveObserver(observer);
 }
 
 void NetworkQualityEstimator::AddRTTAndThroughputEstimatesObserver(
     RTTAndThroughputEstimatesObserver* observer) {
   DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(observer);
   rtt_and_throughput_estimates_observer_list_.AddObserver(observer);
+
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE,
+      base::Bind(&NetworkQualityEstimator::
+                     NotifyRTTAndThroughputEstimatesObserverIfPresent,
+                 weak_ptr_factory_.GetWeakPtr(), observer));
 }
 
 void NetworkQualityEstimator::RemoveRTTAndThroughputEstimatesObserver(
     RTTAndThroughputEstimatesObserver* observer) {
   DCHECK(thread_checker_.CalledOnValidThread());
   rtt_and_throughput_estimates_observer_list_.RemoveObserver(observer);
 }
 
 bool NetworkQualityEstimator::GetRecentHttpRTT(
     const base::TimeTicks& start_time,
@@ skipping 321 matching lines @@
   DCHECK(thread_checker_.CalledOnValidThread());
 
   // TODO(tbansal): Add hysteresis in the notification.
   for (auto& observer : rtt_and_throughput_estimates_observer_list_) {
     observer.OnRTTOrThroughputEstimatesComputed(
         network_quality_.http_rtt(), network_quality_.transport_rtt(),
         network_quality_.downstream_throughput_kbps());
   }
 }
 
+void NetworkQualityEstimator::NotifyEffectiveConnectionTypeObserverIfPresent(
+    EffectiveConnectionTypeObserver* observer) const {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  if (!effective_connection_type_observer_list_.HasObserver(observer))

[RyanSturm, 2016/11/10 23:07:22]

Add testing for Add then Remove observer (not crashing) and ECT = UNKNOWN not
sending an update.

[tbansal1, 2016/11/11 00:49:45]

Done.

+    return;
+  if (effective_connection_type_ == EFFECTIVE_CONNECTION_TYPE_UNKNOWN)
+    return;
+  observer->OnEffectiveConnectionTypeChanged(effective_connection_type_);
+}
+
+void NetworkQualityEstimator::NotifyRTTAndThroughputEstimatesObserverIfPresent(
+    RTTAndThroughputEstimatesObserver* observer) const {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  if (!rtt_and_throughput_estimates_observer_list_.HasObserver(observer))
+    return;
+  observer->OnRTTOrThroughputEstimatesComputed(
+      network_quality_.http_rtt(), network_quality_.transport_rtt(),
+      network_quality_.downstream_throughput_kbps());
+}
+
 void NetworkQualityEstimator::AddNetworkQualitiesCacheObserver(
     nqe::internal::NetworkQualityStore::NetworkQualitiesCacheObserver*
         observer) {
   DCHECK(thread_checker_.CalledOnValidThread());
   network_quality_store_->AddNetworkQualitiesCacheObserver(observer);
 }
 
 void NetworkQualityEstimator::RemoveNetworkQualitiesCacheObserver(
     nqe::internal::NetworkQualityStore::NetworkQualitiesCacheObserver*
         observer) {
   DCHECK(thread_checker_.CalledOnValidThread());
   network_quality_store_->RemoveNetworkQualitiesCacheObserver(observer);
 }
 
 void NetworkQualityEstimator::OnPrefsRead(
     const std::map<nqe::internal::NetworkID,
                    nqe::internal::CachedNetworkQuality> read_prefs) {
   DCHECK(thread_checker_.CalledOnValidThread());
   UMA_HISTOGRAM_COUNTS("NQE.Prefs.ReadSize", read_prefs.size());
   // TODO(tbansal): crbug.com/490870. Incorporate the network quality into the
   // current estimates.
 }
 
 }  // namespace net