Add interface for RTC::Shared, Channel::ChannelNotifier and ChannelMessageRegistrator

[o-u-p]

Feature Request

this will make code more readable and flexible.

[Iñaki Baz Castillo]

I don't know what this is about. Please specify much more hopefully with real code snippets.

[o-u-p]

for example, we can make "void ChannelNotifier::Emit(const std::string& targetId, FBS::Notification::Event event)" to be an interface, and can define some custom implement to send flatbuffer. that will be more flexible.

[Iñaki Baz Castillo]

Please, feel free to write a PR proposal. Honestly we are too busy and won't have time to investigate this.