time: time.Local is always UTC on iOS

[gwik]

Local timezone is hardcoded to UTC on iOS.

https://github.com/golang/go/blob/master/src/time/zoneinfo_ios.go#L39-L42

func initLocal() {
	// TODO(crawshaw): [NSTimeZone localTimeZone]
	localLoc = *UTC
}

As mentioned in the code it should use NSTimeZone localTimeZone to get the current timezone.

cc @eliasnaur @crawshaw

(Same issue on android #20455)

[gwik]

I'll work on it next week.

[gwik]

This adds a dependency to cgo in the time package which is against policy enforced by go/build/deps_test.go and breaks the test.

[bradfitz]

I'd rather avoid modifying the policy for certain ports.

Maybe we can put this in another package (runtime?) and use it from time. That's kinda gross too, though.

@rsc, preferences?

[rsc]

Not this cycle.

[tmm1]

Pinging for a decision on how to proceed here.

[bradfitz]

@tmm1, I'm not sure anybody's thought about it.

It'd be nice to see something that works first, and then we can see how gross it ends up, and where we might shove that grossness. Or maybe it'll look fine.

/cc @eliasnaur @bcmills

[tmm1]

@gwik It sounded like you had a patch for this which was breaking deps_test.go. Care to open a CL with it?

[bradfitz]

/cc @eliasnaur too