Change representation of Wi-Fi calling setting to a String

Change-Id: I3977e8e19102dc026be4677a9e5d5e3c0d3c4a69
diff --git a/res/values/strings.xml b/res/values/strings.xml
index 40b8198..04bd7fe 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -1164,11 +1164,11 @@
 
     <!-- Keep values in sync with android.telephony.TelephonyManager.WifiCallingChoices -->
     <!-- android.telephony.TelephonyManager.WifiCallingChoices.ALWAYS_USE -->
-    <string translatable="false" name="wifi_calling_choices_always_use">0</string>
+    <string translatable="false" name="wifi_calling_choices_always_use">ALWAYS_USE</string>
     <!-- android.telephony.TelephonyManager.WifiCallingChoices.NEVER_USE -->
-    <string translatable="false" name="wifi_calling_choices_never_use">1</string>
+    <string translatable="false" name="wifi_calling_choices_never_use">NEVER_USE</string>
     <!-- android.telephony.TelephonyManager.WifiCallingChoices.ASK_EVERY_TIME -->
-    <string translatable="false" name="wifi_calling_choices_ask_every_time">2</string>
+    <string translatable="false" name="wifi_calling_choices_ask_every_time">ASK_EVERY_TIME</string>
 
     <!-- Title of the dialog to select the phone type for the outgoing call. [CHAR LIMIT=NONE] -->
     <string name ="pick_outgoing_call_phone_type">Place call</string>