Promote Error->map to be a core fn

Question

cljs.repl/Error->map is an imitation of clojure.core/Throwable->map.

It could be cleaned up and promoted to instead be cljs.core/Error->map.

If this were done, a side decision could be pondered and taken on whether it should be named cljs.core/Throwable->map. (You can see arguments both for and against this.)

Answer 1

Reference: https://clojure.atlassian.net/browse/CLJS-3014 (reported by mfikes)