Threads: Improve fallback for clients without Threads

[daniellekirkwood]

Your use case

Instead of including the Root Message in the Reply view for clients without Threads, show the message previous to the response.

@daniellekirkwood to add more info

We know and accept that some clients will not update their versions and therefore will not have this new and improved fallback will not be available to everyone. Those users who do not update their version from the app/play store will still have the previous fallback of seeing the Root message.

[daniellekirkwood]

This was raised in testing on January 22, 2022 as a "fail" and I suspect that's because the work is not yet complete (and wasn't ready for testing). Can you confirm that please, @ismailgulek

[daniellekirkwood]

I think we also need content for what to show when the message has not yet been fetched, as we're currently showing "null". This also is the case on Android: element-hq/element-android#4972

@janogarcia

[daniellekirkwood]

From Aris:

This case would be rare while now we are using as fallback the previous event. However, I implemented that. You can suggest a better text resource:
https://user-images.githubusercontent.com/60798129/151002008-bcaa5ac9-677a-49ff-a9e7-7c1f979436fb.jpg

[janogarcia]

@daniellekirkwood As discussed for Android, I'd suggest changing the placeholder message copy to In reply to a thread if we're not rendering the In reply to @name part.