Restrict Wi-Fi configuration if settings UI is restricted

- Don't launch W-Fi configuration settings if the settings UI is restricted (including guest users).

Bug: 246301667
Test: manual test
make RunSettingsRoboTests ROBOTEST_FILTER=NetworkProviderSettingsTest

Change-Id: Id82498f41765f955e01bb311bb221d26f9574f31

tests/robotests/src/com/android/settings/network/NetworkProviderSettingsTest.java

@@ -751,6 +751,15 @@ public class NetworkProviderSettingsTest {
         assertThat(keys).contains(NetworkProviderSettings.PREF_KEY_WIFI_TOGGLE);
     }
 
+    @Test
+    public void launchConfigNewNetworkFragment_fragmentIsRestricted_ignoreWifiEntry() {
+        mNetworkProviderSettings.mIsRestricted = true;
+
+        mNetworkProviderSettings.launchConfigNewNetworkFragment(mWifiEntry);
+
+        verify(mWifiEntry, never()).getKey();
+    }
+
     @Implements(PreferenceFragmentCompat.class)
     public static class ShadowPreferenceFragmentCompat {