Fixes Cell network setting items grayed out.

Under certain CDMA global roaming conditions, menu items under Cell network 
setting were grayed out.

Bug: 18377054
Change-Id: I72403b072b2ca413d76e82982cb9682a5f219563
diff --git a/res/xml/cdma_options.xml b/res/xml/cdma_options.xml
index d4eaeba..78e3630 100644
--- a/res/xml/cdma_options.xml
+++ b/res/xml/cdma_options.xml
@@ -34,7 +34,7 @@
         android:dialogTitle="@string/cdma_subscription_dialogtitle" />
 
     <PreferenceScreen
-        android:key="button_apn_key"
+        android:key="button_apn_key_cdma"
         android:title="@string/apn_settings"
         android:persistent="false">
 
diff --git a/src/com/android/phone/CdmaOptions.java b/src/com/android/phone/CdmaOptions.java
index 897c797..a04427e 100644
--- a/src/com/android/phone/CdmaOptions.java
+++ b/src/com/android/phone/CdmaOptions.java
@@ -46,7 +46,7 @@
     private static final String BUTTON_CDMA_SUBSCRIPTION_KEY = "cdma_subscription_key";
     private static final String BUTTON_CDMA_ACTIVATE_DEVICE_KEY = "cdma_activate_device_key";
     private static final String BUTTON_CARRIER_SETTINGS_KEY = "carrier_settings_key";
-    private static final String BUTTON_APN_EXPAND_KEY = "button_apn_key";
+    private static final String BUTTON_APN_EXPAND_KEY = "button_apn_key_cdma";
 
     private PreferenceActivity mPrefActivity;
     private PreferenceScreen mPrefScreen;