Create a new non-updatable Wifi filegroup for WifiNetworkScoreCache

WifiNetworkScoreCache will not be part of the Wifi module. Thus,
split it out into a separate filegroup. WifiNetworkScoreCache
will eventually live in framework.jar, while the rest of the Wifi
API surface will live in framework-wifi.jar.

Bug: 144487252
Test: compiles
Change-Id: Id82218204ab62e549b60bcfc41af9eaa305000ce
1 file changed