allow basic logging for http Get err with RegisterErrLogFn

[qbig]

attempt to improve this :

func (g *Group) load(ctx Context, key string, dest Sink) (value ByteView, destPopulated bool, err error) {
// TODO(bradfitz): log the peer's error? keep
// log of the past few for /groupcachez? It's
// probably boring (normal task movement), so not
// worth logging I imagine.

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[qbig]

I signed it!

[googlebot]

CLAs look good, thanks!

[bradfitz]

The "Fn" suffix isn't consistent with the naming elsewhere in Go in general or this file in particular. This file uses "Hook".

Also, end sentences with a period. And http should be HTTP.

[qbig]

cool. will update.

[qbig]

updated

[bradfitz]

What about other context? Do we want to include the key?

[qbig]

Good point! Just wondering how specific errLogFn func(error) should be ?

logErr(fmt.Errorf("g.getFromPeer(ctx, peer, key), ctx: %+v, peer: %+v, key: %+v, err: %+v", ctx, peer, key, err))

or

logErr(ctx, peer, key, err)

[qbig]

updated

[qbig]

updated:)

[qbig]

sorry.. but was there a new review? #81 (review) didn't show anything

[qbig]

@bradfitz any other parts I could improve on this diff ?