Disable the spring charger dialog on locked screen.

ash/system/chromeos/power/tray_power.cc

Index: ash/system/chromeos/power/tray_power.cc
diff --git a/ash/system/chromeos/power/tray_power.cc b/ash/system/chromeos/power/tray_power.cc
index 8bc68d5ec4e9506a16076a88bd6447baf4275d84..9ab2e6fb2672cf347c087235b659be73d9acc560 100644
--- a/ash/system/chromeos/power/tray_power.cc
+++ b/ash/system/chromeos/power/tray_power.cc
@@ -168,7 +168,13 @@ void TrayPower::UpdateAfterShelfAlignmentChange(ShelfAlignment alignment) {
 void TrayPower::OnPowerStatusChanged() {
   RecordChargerType();
 
-  if (PowerStatus::Get()->IsOriginalSpringChargerConnected()) {
+  // TODO(jennyz): Enable showing spring charger dialog on locked screen after
+  // crbug.com/328593 is fixed.
+  user::LoginStatus login_status =
+      Shell::GetInstance()->system_tray_delegate()->GetUserLoginStatus();
+  if (PowerStatus::Get()->IsOriginalSpringChargerConnected() &&
+      (login_status != user::LOGGED_IN_NONE &&
+       login_status != user::LOGGED_IN_LOCKED)) {
     ash::Shell::GetInstance()->system_tray_delegate()->
         ShowSpringChargerReplacementDialog();
   }