WifiNetworkFactory: Check for null package name

Also, consolidated all error check in the utility method:
isRequestWithNetworkSpecifierValid. This is used in both acceptRequest &
needNetworkFor.

Bug: 144102365
Test: Verified that wifi network request related CTS verifier tests pass.
Test: Device boots up and connects to wifi networks
Change-Id: I6eb75932589e709c0d9c51858db0bf6bbce7b550
2 files changed
tree: 2fbc1b3c97f5a40ffcaa5882a7004c2d0bebab05
  1. apex/
  2. service/
  3. PREUPLOAD.cfg