修复v1签名状态下的，读取渠道信息为空的问题

[realityJie]

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[dandycheung]

@realityJie 看了下改进代码，似乎原来代码的判空（channel == null）与修改后的判空（channel.isEmpty）应该 && 一下。

更新：又在 IDE 里看了一眼，== null 永远 false，你的修改没问题。