[WifiNetworkSelector] Consistency of Pre/Post-scan sufficiency

Make the pre-scan sufficiency check use the sufficiency check in
WifiNetworkSelector, because we should not be requesting a connectivity
scan if we are sure that we won't be running network selection.

Also, remove unused LAST_USER_SELECTION_SUFFICIENT_MS.

Bug: 147751334
Test: atest FrameworksWifiTests
Change-Id: I321420f6932654a44a7a904d48b25f6f84865f74
3 files changed
tree: 0da489f317f3d8c0f2fa6eb11cee26a0eb8b63b6
  1. apex/
  2. service/
  3. PREUPLOAD.cfg