NPE in in AppGlobals#getIntCoreSetting

bug:3508658

It ActivityThread#currentActivityThread() is called when
the ActivityThread is not attached it returns null and
AppGlobals#getIntCoreSetting was not checking for that.

Change-Id: I5e00d1947a161ad1e52ecfaa12cbbac3b534a0db

core/java/android/app/AppGlobals.java

@@ -55,6 +55,11 @@ public class AppGlobals {
      * @return The core settings.
      */
     public static int getIntCoreSetting(String key, int defaultValue) {
-        return ActivityThread.currentActivityThread().getIntCoreSetting(key, defaultValue);
+        ActivityThread currentActivityThread = ActivityThread.currentActivityThread();
+        if (currentActivityThread != null) {
+            return currentActivityThread.getIntCoreSetting(key, defaultValue);
+        } else {
+            return defaultValue;
+        }
     }
 }