add setting to control wifi handover

Change-Id: I85a8c8d501238a8115713ca7b018cdac6d0af95a
diff --git a/res/xml/development_prefs.xml b/res/xml/development_prefs.xml
index 98397bf..f30cd07 100644
--- a/res/xml/development_prefs.xml
+++ b/res/xml/development_prefs.xml
@@ -111,6 +111,16 @@
             android:title="@string/wifi_verbose_logging" />
             android:summary="@string/wifi_verbose_logging_summary"/>
 
+        <CheckBoxPreference
+            android:key="wifi_aggressive_handover"
+            android:title="@string/wifi_aggressive_handover" />
+            android:summary="@string/wifi_aggressive_handover_summary"/>
+
+       <CheckBoxPreference
+            android:key="wifi_allow_scan_with_traffic"
+            android:title="@string/wifi_allow_scan_with_traffic" />
+            android:summary="@string/wifi_allow_scan_with_traffic_summary"/>
+
         <ListPreference
             android:key="select_logd_size"
             android:title="@string/select_logd_size_title"