Should only allow saved network UI initialization for once. Bug: 140362368 Test: WifiConfigControllerTest manual: Manually change EAP method and other security fields for a saved Wi-Fi neterprise network. Change-Id: Iddc1dae53849760f43b41b75262358dff6ba09af Merged-In: Iddc1dae53849760f43b41b75262358dff6ba09af