tree f8b4bf4361d9bc0f9cf2f12fb4d4c88da56309b4
parent 9461017a4f5f9085add8850fc082a295bb63131d
author Brian Norris <briannorris@chromium.org> 1592352421 -0700
committer Commit Bot <commit-bot@chromium.org> 1608681762 +0000

shill: wifi: let interface proxy outlive "started"

Disabling the WiFi interface leads to Stop(), which tells wpa_supplicant
to disconnect and tear down the interface; however we don't wait to hear
anything back from wpa_supplicant (e.g., PropertiesChanged -> update
disconnect reason metrics), because we immediately destruct the
SupplicantInterfaceProxy.

Instead, retain the interface proxy until the next Start(). This should
give us time to process any property events, and is otherwise safe
(we're mostly just logging metrics). Add a few enabled() guards on
SupplicantEventDelegateInterface callbacks, so we don't try to
* stash scan results until the next Start()
* perform another full Disconnect (via CurrentBSSChanged()) after we've
  already cleanly torn things down (Stop())

NB: without this change,
network_WiFi_DisconnectReason.disable_client_wifi would fail 100%,
except that b/172219209 causes a lot of false-PASS results.

BUG=b:172217291
TEST=`truncate -s 0 /var/log/net.log` (to work around b/172219209)
      + network_WiFi_DisconnectReason.disable_client_wifi

Disallow-Recycled-Builds: test-failures
Change-Id: Ic6febe34506a7afb568303c9072bf2159992f788
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform2/+/2594267
Tested-by: Brian Norris <briannorris@chromium.org>
Commit-Queue: Brian Norris <briannorris@chromium.org>
Reviewed-by: Matthew Wang <matthewmwang@chromium.org>