Apparently the wifi config can sometimes come back as null
initially when the device auto-connects to a network. This CL simply
makes the controller resilient to that so that it doesn't crash the
app.
Test: robotests
Bug: 73076869
Change-Id: I99098f35df9cd902f5f244a872cce9b71c17c224
1. Add it in wifi detail page
2. Add it in wifi dialog
2. Remove it in "Mobile network" page
Bug: 68030417
Test: RunSettingsRoboTests
Change-Id: I2e001c55f3c6c75a660e429732dfbece97b0ca9e