NullPointerException may be thrown if app is left out of focus for a long time

[TylerMcCraw]

This is more of a task to investigate a NullPointerException in apps that are using the Surelock library.
This seems to be happening for users who leave the app out of focus. Maybe it's left active in their Recent Apps and is killed later on.
We should test leaving the Surelock default dialog open on a Samsung or LG device and leave it active and out of focus for a longer period of time to see if we can replicate the issue.

Fatal Exception: java.lang.NullPointerException: Attempt to invoke interface method 'void com.e.a.f.a(byte[])' on a null object reference
       at com.smashingboxes.surelock.SurelockDefaultDialog$2.run(Unknown Source)
       at android.os.Handler.handleCallback(Handler.java:751)
       at android.os.Handler.dispatchMessage(Handler.java:95)
       at android.os.Looper.loop(Looper.java:154)
       at android.app.ActivityThread.main(ActivityThread.java:6688)
       at java.lang.reflect.Method.invoke(Method.java)
       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1468)
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1358)