Introduced large number of unnecessary re-renders when opening channels, and ideally should not be a part of the channel switching/opening code path. Although this was discovered while trying to investigate an [Android-specific issue](https://mattermost.atlassian.net/browse/MM-22253), this extra code path made it difficult to see what Android is potentially doing differently than iOS.
Functionality originally introduced in #1203.
Conversation for removal is [here](https://community.mattermost.com/core/pl/hfcogf6pr7rw8k3ryq14c69c7e)
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