ARC: Implement SetWifiEnabledState API.

components/arc/net/arc_net_host_impl.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 "components/arc/net/arc_net_host_impl.h"
 
 #include <string>
 #include <vector>
 
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/posix/eintr_wrapper.h"
 #include "base/thread_task_runner_handle.h"
 #include "base/time/time.h"
 #include "chromeos/network/network_handler.h"
 #include "chromeos/network/network_state_handler.h"
+#include "chromeos/network/network_type_pattern.h"
 #include "chromeos/network/network_util.h"
 #include "chromeos/network/onc/onc_utils.h"
 #include "components/arc/arc_bridge_service.h"
 
 namespace {
 
 const int kGetNetworksListLimit = 100;
 
 }  // namespace
 
@@ skipping 106 matching lines @@
     data->networks.push_back(std::move(wc));
   }
 
   callback.Run(std::move(data));
 }
 
 void ArcNetHostImpl::GetWifiEnabledState(
     const GetWifiEnabledStateCallback& callback) {
   bool is_enabled = GetStateHandler()->IsTechnologyEnabled(
       chromeos::NetworkTypePattern::WiFi());
+  callback.Run(is_enabled);
+}
 
-  callback.Run(is_enabled);
+void ArcNetHostImpl::SetWifiEnabledState(
+    bool is_enabled,
+    const SetWifiEnabledStateCallback& callback) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  GetStateHandler()->SetTechnologyEnabled(
+      chromeos::NetworkTypePattern::WiFi(), is_enabled,
+      chromeos::network_handler::ErrorCallback());

[dcheng, 2016/03/15 23:19:43]

Out of curiosity... how are you supposed to know if it succeeded? The lack of
the error callback being called?

[stevenjb, 2016/03/15 23:31:31]

There's an email thread discussing this. Right now you don't know whether or not
it succeeded or failed. The error callback is so that known failures can be
logged, but in theory it could take ~10 seconds before a 'enabled' change
request succeeds or fails, so at the moment the caller needs to observe
technology state changes and decide how to handle that. (The current UI doesn't
do anything special, it just sends the request reflects the current state).

+  callback.Run();
 }
 
 void ArcNetHostImpl::StartScan() {
   GetStateHandler()->RequestScan();
 }
 
 void ArcNetHostImpl::ScanCompleted(const chromeos::DeviceState* /*unused*/) {
   if (arc_bridge_service()->net_version() < 1) {
     VLOG(1) << "ArcBridgeService does not support ScanCompleted.";
     return;
   }
 
   arc_bridge_service()->net_instance()->ScanCompleted();
 }
 
 void ArcNetHostImpl::OnShuttingDown() {
   GetStateHandler()->RemoveObserver(this, FROM_HERE);
 }
 
 }  // namespace arc