Fix WifiScanningServiceImpl stand-alone unit test failure

WifiAsyncChannel and WifiHandler objects use lazy intialization for the
logging objects. WifiInjector.getInstance() may return a null object if
the unit test is run by itself or if earlier tests have not created it.

If the unit tests are able to update these instances with a logging
objects that are not null, then unit test can pass stand-alone.
- Add a method in FrameworkFacade to return new instances of
  WifiAsyncChannel
- Update WifiAsyncChannel to expose setWifiLog() API for testing only
- Call this method on instances of WifiAsyncChannel returned by the mock
  of FrameworkFacade factory to ensure mLog is not null
- Add a method in WifiScanningServiceImpl, also meant for testing only
  to update WifiHandler with logging object
- Change unit tests to call this method after starting scanning service

Bug: 34127212
Test: WifiScanningServiceTest by itself and all unit tests pass
Change-Id: I0bc7a55d6d6862e2360bfb20897828e84358dd39
Merged-In: I0bc7a55d6d6862e2360bfb20897828e84358dd39
4 files changed
tree: b95f0db27ce1b81e949982a01989f7013ca47cac
  1. libwifi_hal/
  2. libwifi_system/
  3. service/
  4. tests/
  5. PREUPLOAD.cfg