use IllegalArgumentException instead of NPE

Signed-off-by: tobiasKaminsky <tobias@kaminsky.me>

src/main/java/com/owncloud/android/ui/dialog/NoteDialogFragment.java

@@ -76,7 +76,7 @@ public class NoteDialogFragment extends DialogFragment implements DialogInterfac
         super.onCreate(savedInstanceState);
 
         if (getArguments() == null) {
-            throw new NullPointerException("Arguments may not be null");
+            throw new IllegalArgumentException("Arguments may not be null");
         }
         share = getArguments().getParcelable(ARG_SHARE);
     }