Reland of [Background Sync] Trigger Background Sync events when Chrome is backgrounded on Android

content/browser/background_sync/background_sync_network_observer.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 "content/browser/background_sync/background_sync_network_observer.h"
 
 #include "base/location.h"
 #include "base/single_thread_task_runner.h"
 #include "base/thread_task_runner_handle.h"
 #include "content/public/browser/browser_thread.h"
 
 namespace content {
 
+// static
+bool BackgroundSyncNetworkObserver::ignore_network_change_notifier_ = false;
+
+// static
+void BackgroundSyncNetworkObserver::SetIgnoreNetworkChangeNotifierForTests(
+    bool ignore) {
+  ignore_network_change_notifier_ = ignore;
+}
+
 BackgroundSyncNetworkObserver::BackgroundSyncNetworkObserver(
     const base::Closure& network_changed_callback)
     : connection_type_(net::NetworkChangeNotifier::GetConnectionType()),
       network_changed_callback_(network_changed_callback) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 
   net::NetworkChangeNotifier::AddNetworkChangeObserver(this);
 }
 
 BackgroundSyncNetworkObserver::~BackgroundSyncNetworkObserver() {
@@ skipping 16 matching lines @@
              !net::NetworkChangeNotifier::IsConnectionCellular(
                  connection_type_);
     case NETWORK_STATE_ONLINE:
       return connection_type_ != net::NetworkChangeNotifier::CONNECTION_NONE;
   }
 
   NOTREACHED();
   return false;
 }
 
-void BackgroundSyncNetworkObserver::NotifyNetworkChanged() {
-  DCHECK_CURRENTLY_ON(BrowserThread::IO);
-
-  base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE,
-                                                network_changed_callback_);
-}
-
 void BackgroundSyncNetworkObserver::OnNetworkChanged(
     net::NetworkChangeNotifier::ConnectionType connection_type) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 
+  if (ignore_network_change_notifier_)
+    return;
+  NotifyManagerIfNetworkChanged(connection_type);
+}
+
+void BackgroundSyncNetworkObserver::NotifyManagerIfNetworkChanged(
+    net::NetworkChangeNotifier::ConnectionType connection_type) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
   if (connection_type == connection_type_)
     return;
 
   connection_type_ = connection_type;
   NotifyNetworkChanged();
 }
 
+void BackgroundSyncNetworkObserver::NotifyNetworkChanged() {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+
+  base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE,
+                                                network_changed_callback_);
+}
+
 }  // namespace content