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

android_webview/browser/net/aw_network_change_notifier_factory.h

+// 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.
+
+#ifndef ANDROID_WEBVIEW_NET_AW_NETWORK_CHANGE_NOTIFIER_FACTORY_H_
+#define ANDROID_WEBVIEW_NET_AW_NETWORK_CHANGE_NOTIFIER_FACTORY_H_
+
+#include "net/android/network_change_notifier_delegate_android.h"
+#include "net/base/network_change_notifier_factory.h"
+
+namespace net {
+class NetworkChangeNotifier;
+class NetworkChangeNotifierDelegateAndroid;
+}
+
+namespace android_webview {
+
+// AwNetworkChangeNotifierFactory creates WebView-specific specialization of
+// NetworkChangeNotifier. See aw_network_change_notifier.h for more details.
+class AwNetworkChangeNotifierFactory :
+    public net::NetworkChangeNotifierFactory {
+ public:
+  // Must be called on the JNI thread.
+  AwNetworkChangeNotifierFactory();
+
+  // Must be called on the JNI thread.
+  ~AwNetworkChangeNotifierFactory() override;
+
+  // NetworkChangeNotifierFactory:
+  net::NetworkChangeNotifier* CreateInstance() override;
+
+ private:
+  // Delegate passed to the instances created by this class.
+  net::NetworkChangeNotifierDelegateAndroid delegate_;
+
+  DISALLOW_COPY_AND_ASSIGN(AwNetworkChangeNotifierFactory);
+};
+
+}  // namespace android_webview
+
+#endif  // ANDROID_WEBVIEW_NET_AW_NETWORK_CHANGE_NOTIFIER_FACTORY_H_