Modules: return owned value with ConnectionReader

[CharlyCst]

Crate

ibc

Summary

Return Option<ConnectionEnd> instead of Option<&ConnectionEnd> in ConnectionReader::connection_end.

Problem Definition

There are two motivations for this change:

1. The ConnectionReader trait's methods mostly return owned values (client_state returns a Option<AnyClientState>, host_consensus_state returns an owned value too), the only exception being connection_end which returns an Option<&ConnectionEnd>. For the sake of consistency, all methods should return either owned or borrowed values.
   The ClientReader trait's methods return owned values, too.
2. More importantly, as I expect that most stores will use a raw byte storage format (tell me if I'm wrong) and thus need to de-serialize and allocate a new struct, it makes more sense to return objects rather than references. Due to the ownership system, returning data owned by the connection_end function can probably be worked around, but it doesn't seems to be ideal.

Proposal

You can see the required changes here.

Note that is is a breaking change.

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[romac]

Agreed, on both points! 👍