Add a feature flag for network service and about:flags entry for it.

android_webview/renderer/aw_content_renderer_client.cc

 // Copyright 2012 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/renderer/aw_content_renderer_client.h"
 
 #include <vector>
 
 #include "android_webview/common/aw_switches.h"
 #include "android_webview/common/render_view_messages.h"
@@ skipping 15 matching lines @@
 #include "components/autofill/content/renderer/autofill_agent.h"
 #include "components/autofill/content/renderer/password_autofill_agent.h"
 #include "components/printing/renderer/print_web_view_helper.h"
 #include "components/safe_browsing/renderer/websocket_sb_handshake_throttle.h"
 #include "components/spellcheck/spellcheck_build_features.h"
 #include "components/supervised_user_error_page/gin_wrapper.h"
 #include "components/supervised_user_error_page/supervised_user_error_page_android.h"
 #include "components/visitedlink/renderer/visitedlink_slave.h"
 #include "components/web_restrictions/interfaces/web_restrictions.mojom.h"
 #include "content/public/child/child_thread.h"
-#include "content/public/common/content_switches.h"
+#include "content/public/common/content_features.h"
 #include "content/public/common/service_manager_connection.h"
 #include "content/public/common/service_names.mojom.h"
 #include "content/public/common/simple_connection_filter.h"
 #include "content/public/common/url_constants.h"
 #include "content/public/renderer/document_state.h"
 #include "content/public/renderer/navigation_state.h"
 #include "content/public/renderer/render_frame.h"
 #include "content/public/renderer/render_thread.h"
 #include "content/public/renderer/render_view.h"
 #include "net/base/escape.h"
@@ skipping 281 matching lines @@
                        base::CompareCase::INSENSITIVE_ASCII)) {
       return true;
     }
   }
   return false;
 }
 
 bool AwContentRendererClient::UsingSafeBrowsingMojoService() {
   if (safe_browsing_)
     return true;
-  if (!base::CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kEnableNetworkService)) {
+  if (!base::FeatureList::IsEnabled(features::kNetworkService)) {

[Alexei Svitkine (slow), 2017/06/29 13:58:24]

Nit: No {}'s

[jam, 2017/06/30 17:21:18]

Done.

     return false;
   }
   RenderThread::Get()->GetConnector()->BindInterface(
       content::mojom::kBrowserServiceName, &safe_browsing_);
   return true;
 }
 
 }  // namespace android_webview