Fix finishing recurrence

app/src/main/java/com/todoroo/astrid/repeats/RepeatTaskHelper.kt

@@ -81,7 +81,11 @@ class RepeatTaskHelper @Inject constructor(
     }
 
     suspend fun undoRepeat(task: Task, oldDueDate: Long) {
-        task.completionDate = 0L
+        if (task.completionDate > 0) {
+            task.completionDate = 0
+            taskDao.save(task)
+            return
+        }
         try {
             val recur = newRecur(task.recurrence!!)
             val count = recur.count

app/src/main/java/com/todoroo/astrid/service/TaskCompleter.kt

@@ -84,11 +84,14 @@ class TaskCompleter @Inject internal constructor(
 
                         if (caldavDao.getAccountForTask(task.id)?.isSuppressRepeatingTasks != true) {
                             repeatTaskHelper.handleRepeat(task)
+                            if (task.completionDate == 0L) {
+                                // un-complete children
                                 setComplete(task, false)
                             }
                         }
                     }
                 }
+        }
         if (completed && notificationManager.currentInterruptionFilter == INTERRUPTION_FILTER_ALL) {
             preferences
                 .completionSound