Fixed a rare crash in reminder dialog

astrid/plugin-src/com/todoroo/astrid/reminders/ReminderDialog.java

@@ -116,6 +116,7 @@ public class ReminderDialog extends Dialog {
             @Override
             public void onClick(View arg0) {
                 Task task = taskService.fetchById(taskId, Task.ID, Task.REMINDER_LAST, Task.SOCIAL_REMINDER);
+                if (task != null)
                     taskService.setComplete(task, true);
                 activity.sendBroadcast(new Intent(AstridApiConstants.BROADCAST_EVENT_REFRESH));
                 Toast.makeText(activity,