code review 94170043: runtime: say when a goroutine is locked to OS thread

runtime: say when a goroutine is locked to OS thread
Say when a goroutine is locked to OS thread in crash reports
and goroutine profiles.
It can be useful to understand what goroutines consume OS threads
(syscall and locked), e.g. if you forget to call UnlockOSThread
or leak locked goroutines.

[dvyukov, 2014-06-22 05:50:52]

Hello golang-codereviews@googlegroups.com (cc: rsc@golang.org),

I'd like you to review this change to
https://dvyukov%40google.com@code.google.com/p/go/

[rsc, 2014-06-26 14:56:27]

LGTM

[dvyukov, 2014-06-26 18:47:24]

*** Submitted as https://code.google.com/p/go/source/detail?r=c53623a08752 ***

runtime: say when a goroutine is locked to OS thread
Say when a goroutine is locked to OS thread in crash reports
and goroutine profiles.
It can be useful to understand what goroutines consume OS threads
(syscall and locked), e.g. if you forget to call UnlockOSThread
or leak locked goroutines.

R=golang-codereviews
CC=golang-codereviews, rsc
https://codereview.appspot.com/94170043

[gobot, 2014-06-26 18:57:56]

This CL appears to have broken the openbsd-386-rootbsd builder.
See http://build.golang.org/log/006ce117e176d0632bfc8ae7625d2c1a25cc9da3