Fixed a SIM Cards crash.

+ Added a check if getActiveSubscriptionInfoList returns null.

Bug: 18634751
Change-Id: Ib6012816c26525a61fb199912d06d6c1572e0fd6
diff --git a/src/com/android/settings/sim/SimDialogActivity.java b/src/com/android/settings/sim/SimDialogActivity.java
index cf3ccdf..6aceb46 100644
--- a/src/com/android/settings/sim/SimDialogActivity.java
+++ b/src/com/android/settings/sim/SimDialogActivity.java
@@ -152,7 +152,7 @@
         final SubscriptionManager subscriptionManager = SubscriptionManager.from(context);
         final List<SubscriptionInfo> subInfoList =
             subscriptionManager.getActiveSubscriptionInfoList();
-        final int selectableSubInfoLength = subInfoList.size();
+        final int selectableSubInfoLength = subInfoList == null ? 0 : subInfoList.size();
 
         final DialogInterface.OnClickListener selectionListener =
                 new DialogInterface.OnClickListener() {