Add Network Quality Estimator (NQE) pref manager

net/nqe/network_qualities_prefs_manager.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_qualities_prefs_manager.h"
+
+#include <utility>
+
+#include "base/bind.h"
+#include "base/threading/thread_checker.h"
+#include "base/values.h"
+#include "net/nqe/cached_network_quality.h"
+#include "net/nqe/network_quality_estimator.h"
+
+namespace net {
+
+NetworkQualitiesPrefsManager::NetworkQualitiesPrefsManager(
+    std::unique_ptr<PrefDelegate> pref_delegate)
+    : pref_delegate_(std::move(pref_delegate)),
+      pref_task_runner_(base::ThreadTaskRunnerHandle::Get()),

[Not at Google. Contact bengr, 2016/09/15 22:46:57]

Import what you use:
#include "base/sequenced_task_runner.h"
#include "base/threading/thread_task_runner_handle.h"

[tbansal1, 2016/09/17 00:26:36]

Done.

+      network_quality_estimator_(nullptr),
+      pref_weak_ptr_factory_(this) {
+  DCHECK(pref_delegate_);
+
+  pref_weak_ptr_ = pref_weak_ptr_factory_.GetWeakPtr();
+}
+
+NetworkQualitiesPrefsManager::~NetworkQualitiesPrefsManager() {
+  DCHECK(network_task_runner_->RunsTasksOnCurrentThread());
+  network_quality_estimator_->RemoveNetworkQualitiesCacheObserver(this);
+}
+
+void NetworkQualitiesPrefsManager::InitializeOnNetworkThread(
+    NetworkQualityEstimator* network_quality_estimator) {
+  DCHECK(!network_task_runner_);
+  DCHECK(network_quality_estimator);
+
+  network_task_runner_ = base::ThreadTaskRunnerHandle::Get();
+
+  network_quality_estimator_ = network_quality_estimator;
+
+  network_quality_estimator_->AddNetworkQualitiesCacheObserver(this);
+}
+
+void NetworkQualitiesPrefsManager::OnChangeInCachedNetworkQuality(
+    const nqe::internal::NetworkID& network_id,
+    const nqe::internal::CachedNetworkQuality& cached_network_quality) {
+  DCHECK(network_task_runner_->RunsTasksOnCurrentThread());
+
+  // Notify |this| on the pref thread.
+  pref_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&NetworkQualitiesPrefsManager::
+                     OnChangeInCachedNetworkQualityOnPrefThread,
+                 pref_weak_ptr_, network_id, cached_network_quality));
+}
+
+void NetworkQualitiesPrefsManager::ShutdownOnPrefThread() {
+  DCHECK(pref_task_runner_->RunsTasksOnCurrentThread());
+  pref_delegate_.reset();
+}
+
+void NetworkQualitiesPrefsManager::OnChangeInCachedNetworkQualityOnPrefThread(
+    const nqe::internal::NetworkID& network_id,
+    const nqe::internal::CachedNetworkQuality& cached_network_quality) {
+  // The prefs can only be written on the pref thread.
+  DCHECK(pref_task_runner_->RunsTasksOnCurrentThread());
+
+  base::DictionaryValue dictionary_value;
+  dictionary_value.SetString(
+      network_id.ToString(),
+      GetNameForEffectiveConnectionType(
+          cached_network_quality.effective_connection_type()));
+
+  // Notify the pref delegate so that it updates the prefs on the disk.
+  pref_delegate_->SetDictionaryValue(dictionary_value);
+}
+
+}  // namespace net