Clean up ICU data tables on shutdown.

Clean up ICU data tables on shutdown.

This is only used by d8 if compiled with external data tables, or an
embedder that uses external data tables and v8's version of ICU.

BUG=none
R=svenpanne@chromium.org
LOG=n

Committed: https://code.google.com/p/v8/source/detail?r=20283

[Sven Panne, 2014-03-26 07:44:47]

https://codereview.chromium.org/210973007/diff/1/src/icu_util.cc
File src/icu_util.cc (right):

https://codereview.chromium.org/210973007/diff/1/src/icu_util.cc#newcode103
src/icu_util.cc:103: atexit(free_icu_data_ptr);
Hmmm, using atexit is always a kind of a hack, and it would be the only place
where we use it in v8. InitializeICU has to be called explicitly, so I would
very much prefer an explicit matching "ShutdownICU" (or whatever we call it).

[jochen (gone - plz use gerrit), 2014-03-26 12:19:24]

On 2014/03/26 07:44:47, Sven Panne wrote:
> https://codereview.chromium.org/210973007/diff/1/src/icu_util.cc
> File src/icu_util.cc (right):
> 
> https://codereview.chromium.org/210973007/diff/1/src/icu_util.cc#newcode103
> src/icu_util.cc:103: atexit(free_icu_data_ptr);
> Hmmm, using atexit is always a kind of a hack, and it would be the only place
> where we use it in v8. InitializeICU has to be called explicitly, so I would
> very much prefer an explicit matching "ShutdownICU" (or whatever we call it).

not sure.

There's only one place where the program starts, but arbitrary many where it can
end :-/

I'd rather just leak the memory (that's what we do in chromium as well).

[Sven Panne, 2014-03-26 12:39:00]

LGTM after offline discussion :-)

[jochen (gone - plz use gerrit), 2014-03-26 15:46:16]

Committed patchset #1 manually as r20283 (presubmit successful).