Fix NPE when APPWIDGET_PICK has no value for EXTRA_CUSTOM_INFO

Fixes http://b/issue?id=2315370

Change-Id: Ib5077943f40e66f1d6d4121416d0a36f7bdcfc9d
diff --git a/src/com/android/settings/AppWidgetPickActivity.java b/src/com/android/settings/AppWidgetPickActivity.java
index cddc687..176ac80 100644
--- a/src/com/android/settings/AppWidgetPickActivity.java
+++ b/src/com/android/settings/AppWidgetPickActivity.java
@@ -167,6 +167,7 @@
      */
     void putAppWidgetItems(List<AppWidgetProviderInfo> appWidgets,
             List<Bundle> customExtras, List<PickAdapter.Item> items) {
+        if (appWidgets == null) return;
         final int size = appWidgets.size();
         for (int i = 0; i < size; i++) {
             AppWidgetProviderInfo info = appWidgets.get(i);