Add old_state parameter to CustomButton::StateChanged

ash/common/system/chromeos/network/network_state_list_detailed_view.cc

 // Copyright (c) 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 "ash/common/system/chromeos/network/network_state_list_detailed_view.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "ash/common/ash_constants.h"
@@ skipping 245 matching lines @@
 
   void SetVisible(bool visible) override {
     layer()->GetAnimator()->StopAnimating();  // Stop any previous animation.
     ui::ScopedLayerAnimationSettings animation(layer()->GetAnimator());
     animation.SetTransitionDuration(
         base::TimeDelta::FromMilliseconds(kFadeIconMs));
     layer()->SetOpacity(visible ? 1.0 : 0.0);
   }
 
   // views::CustomButton
-  void StateChanged() override {
+  void StateChanged(ButtonState old_state) override {
     if (state() == STATE_HOVERED || state() == STATE_PRESSED) {
       set_background(views::Background::CreateSolidBackground(
           kTrayPopupHoverBackgroundColor));
     } else {
       set_background(nullptr);
     }
     SchedulePaint();
   }
 
  private:
@@ skipping 766 matching lines @@
       UMA_STATUS_AREA_NETWORK_JOIN_OTHER_CLICKED);
   WmShell::Get()->system_tray_controller()->ShowNetworkCreate(shill::kTypeWifi);
 }
 
 void NetworkStateListDetailedView::RelayoutScrollList() {
   scroller()->Layout();
 }
 
 }  // namespace tray
 }  // namespace ash