clearSubChannelMessages

Based on ClearSubChannelMessagesParams.policy determine Clear range:

Notification level settings

val params = ClearSubChannelMessagesParams(
timestamp = System.currentTimeMillis() - 86400000,
policy = MessageOperationPolicy.LOCAL_REMOTE
)
subChannel.clearMessages(params) { error ->
if (error == null) {
@param handler Operation result callback. Success when error null
}
}

first delete Local, then delete Remote

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