Add old_state parameter to CustomButton::StateChanged

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

Index: ash/common/system/chromeos/network/network_state_list_detailed_view.cc
diff --git a/ash/common/system/chromeos/network/network_state_list_detailed_view.cc b/ash/common/system/chromeos/network/network_state_list_detailed_view.cc
index 80908899ba9ce84d08740f14c5bd672c4d962234..e1f58c138634691b34b2933646f3eaeb345fb7bf 100644
--- a/ash/common/system/chromeos/network/network_state_list_detailed_view.cc
+++ b/ash/common/system/chromeos/network/network_state_list_detailed_view.cc
@@ -263,7 +263,7 @@ class InfoIcon : public views::ImageButton {
   }
 
   // views::CustomButton
-  void StateChanged() override {
+  void StateChanged(ButtonState old_state) override {
     if (state() == STATE_HOVERED || state() == STATE_PRESSED) {
       set_background(views::Background::CreateSolidBackground(
           kTrayPopupHoverBackgroundColor));