[CrOS Tether] Disconnect cleanly from active Tether networks when the user logs out or the Tether c…

chromeos/components/tether/pref_names.cc

Index: chromeos/components/tether/pref_names.cc
diff --git a/chromeos/components/tether/pref_names.cc b/chromeos/components/tether/pref_names.cc
index 1e9b0cb597eb59ae61a30e8b83faa04d3d613836..387aa2c2f96b51c639406cad0883e159a457e4a7 100644
--- a/chromeos/components/tether/pref_names.cc
+++ b/chromeos/components/tether/pref_names.cc
@@ -24,6 +24,9 @@ const char kTetherNetworkGuid[] = "tether.tether_network_id";
 
 const char kWifiNetworkGuid[] = "tether.wifi_network_id";
 
+const char kDisconnectingWifiNetworkGuid[] =
+    "tether.disconnecting_wifi_network_id";
+
 }  // namespace prefs
 
 }  // namespace tether