[Android WebView] Implement support for Network Information API and enable it.

android_webview/browser/net/aw_network_change_notifier.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 "android_webview/browser/net/aw_network_change_notifier.h"
+
+namespace android_webview {
+
+AwNetworkChangeNotifier::~AwNetworkChangeNotifier() {
+  delegate_->RemoveObserver(this);
+}
+
+net::NetworkChangeNotifier::ConnectionType
+AwNetworkChangeNotifier::GetCurrentConnectionType() const {
+  return delegate_->GetCurrentConnectionType();
+}
+
+void AwNetworkChangeNotifier::GetCurrentMaxBandwidthAndConnectionType(
+    double* max_bandwidth_mbps,
+    ConnectionType* connection_type) const {
+  delegate_->GetCurrentMaxBandwidthAndConnectionType(max_bandwidth_mbps,
+                                                     connection_type);
+}
+
+bool AwNetworkChangeNotifier::AreNetworkHandlesCurrentlySupported() const {
+  return false;
+}
+
+void AwNetworkChangeNotifier::GetCurrentConnectedNetworks(
+    NetworkChangeNotifier::NetworkList* networks) const {
+  delegate_->GetCurrentlyConnectedNetworks(networks);
+}
+
+net::NetworkChangeNotifier::ConnectionType
+AwNetworkChangeNotifier::GetCurrentNetworkConnectionType(
+    NetworkHandle network) const {
+  return delegate_->GetNetworkConnectionType(network);
+}
+
+net::NetworkChangeNotifier::NetworkHandle
+AwNetworkChangeNotifier::GetCurrentDefaultNetwork() const {
+  return delegate_->GetCurrentDefaultNetwork();
+}
+
+void AwNetworkChangeNotifier::OnConnectionTypeChanged() {}
+
+void AwNetworkChangeNotifier::OnMaxBandwidthChanged(
+    double max_bandwidth_mbps,
+    ConnectionType type) {
+  // Note that this callback is sufficient for Network Information API because
+  // it also occurs on type changes (see network_change_notifier.h).
+  NetworkChangeNotifier::NotifyObserversOfMaxBandwidthChange(max_bandwidth_mbps,
+                                                             type);
+}
+
+void AwNetworkChangeNotifier::OnNetworkConnected(NetworkHandle network) {}
+void AwNetworkChangeNotifier::OnNetworkSoonToDisconnect(
+    NetworkHandle network) {}
+void AwNetworkChangeNotifier::OnNetworkDisconnected(
+    NetworkHandle network) {}
+void AwNetworkChangeNotifier::OnNetworkMadeDefault(NetworkHandle network){}
+
+AwNetworkChangeNotifier::AwNetworkChangeNotifier(
+    net::NetworkChangeNotifierDelegateAndroid* delegate)
+    : net::NetworkChangeNotifier(DefaultNetworkChangeCalculatorParams()),
+      delegate_(delegate) {
+  delegate_->AddObserver(this);
+}
+
+// static
+net::NetworkChangeNotifier::NetworkChangeCalculatorParams
+AwNetworkChangeNotifier::DefaultNetworkChangeCalculatorParams() {
+  net::NetworkChangeNotifier::NetworkChangeCalculatorParams params;
+  // Use defaults as in network_change_notifier_android.cc
+  params.ip_address_offline_delay_ = base::TimeDelta::FromSeconds(1);
+  params.ip_address_online_delay_ = base::TimeDelta::FromSeconds(1);
+  params.connection_type_offline_delay_ = base::TimeDelta::FromSeconds(0);
+  params.connection_type_online_delay_ = base::TimeDelta::FromSeconds(0);
+  return params;
+}
+
+}  // namespace android_webview