WifiScannerImpl: PNO implementation (Part 1)

1. Immplementation of the PNO interface in WifiScannerImpl for
setting/resetting the PNO list.
  a. For supplicant based PNO, setting the pno list will also
  trigger the scan and we don't scan any background scans.
  b. For HAL based PNO, we set the pno list and then schedule a normal
  background scan.
2. Plumbing of the OnPnoNetworkFound callback to the client.

TODO's:
1.  Will need to integrate the PNO monitor notifcations in
SupplicantWifiScannerImpl to raise OnPnoNetworkFound callbacks.

BUG: 27167559
Change-Id: I8859a419b37b9cb125a710fb67ae1b62db7f779d
TEST: Compiles & unit-test passes
5 files changed
tree: 9e8f347fab576c361dc9b5f7cd6623663e5e8aef
  1. service/
  2. tests/