[DevTools] Network.emulateNetworkConditions now affects NetworkStateNotifier.

chrome/browser/devtools/devtools_network_protocol_handler.cc

 // Copyright 2014 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 "chrome/browser/devtools/devtools_network_protocol_handler.h"
 
 #include <utility>
 
 #include "base/values.h"
 #include "chrome/browser/devtools/devtools_network_conditions.h"
@@ skipping 74 matching lines @@
         command_id, names::kParamUploadThroughput);
   }
   if (upload_throughput < 0.0)
     upload_throughput = 0.0;
 
   std::unique_ptr<DevToolsNetworkConditions> conditions(
       new DevToolsNetworkConditions(offline, latency, download_throughput,
                                     upload_throughput));
 
   UpdateNetworkState(agent_host, std::move(conditions));
-
-  std::unique_ptr<base::DictionaryValue> result(new base::DictionaryValue());
-  return DevToolsProtocol::CreateSuccessResponse(command_id, std::move(result));
+  return nullptr; // Fall-through.
 }
 
 void DevToolsNetworkProtocolHandler::UpdateNetworkState(
     content::DevToolsAgentHost* agent_host,
     std::unique_ptr<DevToolsNetworkConditions> conditions) {
   Profile* profile = Profile::FromBrowserContext(
       agent_host->GetBrowserContext());
   if (!profile)
     return;
   profile->GetDevToolsNetworkControllerHandle()->SetNetworkState(
       agent_host->GetId(), std::move(conditions));
 }
 
 void DevToolsNetworkProtocolHandler::DevToolsAgentStateChanged(
     content::DevToolsAgentHost* agent_host,
     bool attached) {
   std::unique_ptr<DevToolsNetworkConditions> conditions;
   if (attached)
     conditions.reset(new DevToolsNetworkConditions());
   UpdateNetworkState(agent_host, std::move(conditions));
 }