FirebaseMessaging.sendEach has a limit of 500 messages

检查 src/main/java/com/google/firebase/messaging/FirebaseMessaging.java 第 226 行附近的代码，从 FirebaseMessaging.sendEach 所应用的验证开始。确认 500 条消息的限制是否仍然适用，然后找到相关测试并更新它们，以便通过处理一个大于 500 个元素的列表且不出现此验证错误来证明已完成。

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• Firebase SDK version: 9.4.2
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[REQUIRED] Step 3: Describe the problem

sendEach has a limit of 500 messages, this limit is probably a leftover from sendAll which no longer works. It's not really logical to have this limit anymore.

https://github.com/firebase/firebase-admin-java/blob/master/src/main/java/com/google/firebase/messaging/FirebaseMessaging.java#L226

Steps to reproduce:

Create a list with over 500 messages / push notifications. Call FirebaseMessaging.sendEach with the list. An error is thrown that there is over 500 messages in the array.
What happened? How can we make the problem occur?
This could be a description, log/console output, etc.

Relevant Code:

    checkArgument(immutableMessages.size() <= 500,
        "messages list must not contain more than 500 elements");

https://github.com/firebase/firebase-admin-java/blob/master/src/main/java/com/google/firebase/messaging/FirebaseMessaging.java#L226