push token update when users migrate their apps to new devices

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Push notification tokens might be changed when users migrate their profiles to another mobile devices. Therefore, creating a specific message to update token information by sending secure messages are required. Similar to secure introduction, we have to create another special type of message to update push token information in app database.

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User devices are required to upload their push token information when they perform backup. Once app migration is completed, the app detects old push token and begin token update through sending new token attached with messages to all recipients where the app keeps.