Disable Network button in lock screen.

Changing network settings is not allowed in lock screen. In previous
implementation, network button is enabled and able to click even in lock screen.

TEST=manual
BUG=865333

Change-Id: I1986b353d1cdbe698a5390a7861cdf804cc5990d
Reviewed-on: https://chromium-review.googlesource.com/1156189Reviewed-by: Tetsui Ohkubo <tetsui@chromium.org>
Reviewed-by: Yoshiki Iguchi <yoshiki@chromium.org>
Commit-Queue: Toshiki Kikuchi <toshikikikuchi@google.com>
Cr-Commit-Position: refs/heads/master@{#579742}

ash/system/network/network_feature_pod_controller.cc

@@ -5,6 +5,8 @@
 #include "ash/system/network/network_feature_pod_controller.h"
 
 #include "ash/resources/vector_icons/vector_icons.h"
+#include "ash/session/session_controller.h"
+#include "ash/shell.h"
 #include "ash/strings/grit/ash_strings.h"
 #include "ash/system/network/network_feature_pod_button.h"
 #include "ash/system/unified/unified_system_tray_controller.h"
@@ -62,6 +64,7 @@ NetworkFeaturePodController::~NetworkFeaturePodController() = default;
 FeaturePodButton* NetworkFeaturePodController::CreateButton() {
   DCHECK(!button_);
   button_ = new NetworkFeaturePodButton(this);
+  UpdateButton();
   return button_;
 }
 
@@ -84,4 +87,10 @@ SystemTrayItemUmaType NetworkFeaturePodController::GetUmaType() const {
   return SystemTrayItemUmaType::UMA_NETWORK;
 }
 
+void NetworkFeaturePodController::UpdateButton() {
+  // Network setting is always immutable in lock screen.
+  SessionController* session_controller = Shell::Get()->session_controller();
+  button_->SetEnabled(!session_controller->IsScreenLocked());
+}
+
 }  // namespace ash

ash/system/network/network_feature_pod_controller.h

@@ -26,6 +26,8 @@ class NetworkFeaturePodController : public FeaturePodControllerBase {
   SystemTrayItemUmaType GetUmaType() const override;
 
  private:
+  void UpdateButton();
+
   // Unowned.
   UnifiedSystemTrayController* tray_controller_;
   FeaturePodButton* button_ = nullptr;