Crash online reader

[cylonu87]

Pressing a button to change the current page (next, prev, last, first) will crash the reader if the number of pages is not know yet.

java.lang.NullPointerException: Attempt to invoke virtual method 'int net.android.mdm.activity.OnlineReaderActivity$d.getPageCount()' on a null object reference
    at net.android.mdm.activity.OnlineReaderActivity.a(OnlineReaderActivity.java:785)
    at net.android.mdm.activity.OnlineReaderActivity.a(OnlineReaderActivity.java:71)
    at net.android.mdm.activity.OnlineReaderActivity$4.onClick(OnlineReaderActivity.java:1137)



java.lang.NullPointerException: Attempt to invoke virtual method 'int net.android.mdm.activity.OnlineReaderActivity$d.getPageCount()' on a null object reference
    at net.android.mdm.activity.OnlineReaderActivity$6.onClick(OnlineReaderActivity.java:1154)