Fix calculation of Access Point Level.

Bug: b/35854026
Test: make RunSettingsRoboTests
Change-Id: I5287e8c7b46a463cfa25659c756f6ca9175cb68c

res/values/arrays.xml

@@ -319,6 +319,7 @@
     <!-- Match this with drawable.wifi_signal. --> <skip />
     <!-- Wi-Fi settings. The signal strength a Wi-Fi network has. -->
     <string-array name="wifi_signal">
+        <item>Poor</item>
         <item>Poor</item>
         <item>Fair</item>
         <item>Good</item>

src/com/android/settings/wifi/WifiSettings.java

@@ -642,7 +642,7 @@ public class WifiSettings extends RestrictedSettingsFragment
                 for (; index < numAccessPointsToShow; index++) {
                     AccessPoint accessPoint = accessPoints.get(index);
                     // Ignore access points that are out of range.
-                    if (accessPoint.getLevel() != -1) {
+                    if (accessPoint.isReachable()) {
                         String key = accessPoint.getBssid();
                         if (TextUtils.isEmpty(key)) {
                             key = accessPoint.getSsidStr();