Disable legacy poor Network detection
Bug:18723206
Legacy poor network detection was removed from L settings but can still be enabled during an upgrade if it had been manually enabled by user, now really disable it.

Change-Id: I661b326c6f5dfacfcc5582cea14dc52501740367
diff --git a/service/java/com/android/server/wifi/WifiWatchdogStateMachine.java b/service/java/com/android/server/wifi/WifiWatchdogStateMachine.java
index 181e043..0ef18e6 100644
--- a/service/java/com/android/server/wifi/WifiWatchdogStateMachine.java
+++ b/service/java/com/android/server/wifi/WifiWatchdogStateMachine.java
@@ -435,15 +435,8 @@
     private void updateSettings() {
         if (DBG) logd("Updating secure settings");
 
-        // disable poor network avoidance
-        if (sWifiOnly) {
-            logd("Disabling poor network avoidance for wi-fi only device");
-            mPoorNetworkDetectionEnabled = false;
-        } else {
-            mPoorNetworkDetectionEnabled = getSettingsGlobalBoolean(mContentResolver,
-                    Settings.Global.WIFI_WATCHDOG_POOR_NETWORK_TEST_ENABLED,
-                    WifiManager.DEFAULT_POOR_NETWORK_AVOIDANCE_ENABLED);
-        }
+        // Unconditionally disable poor network avoidance, since this mechanism is obsolete
+        mPoorNetworkDetectionEnabled = false;
     }
 
     /**