Reuse thread when writing stdout/stderr on Windows.

Reuse thread when writing stdout/stderr on Windows.

BUG=https://code.google.com/p/dart/issues/detail?id=13541

[Søren Gjesse, 2013-10-02 08:49:22]

LGTM with comments

https://codereview.chromium.org/25631005/diff/1/runtime/bin/eventhandler_win.cc
File runtime/bin/eventhandler_win.cc (right):

https://codereview.chromium.org/25631005/diff/1/runtime/bin/eventhandler_win....
runtime/bin/eventhandler_win.cc:563: 
Please add these static variables to the Windows EventHandlerImplementation
class.

https://codereview.chromium.org/25631005/diff/1/runtime/bin/eventhandler_win....
runtime/bin/eventhandler_win.cc:637: // Double-checked locking, to avoid taking
the lock in most cases.
You need to hold the lock before accessing shared variables. There is no
guarantee that these reads are atomic (in almost all cases they are, but the
compiler might fool us).

https://codereview.chromium.org/25631005/diff/1/runtime/bin/eventhandler_win....
runtime/bin/eventhandler_win.cc:1039:
EventHandlerImplementation::~EventHandlerImplementation() {
Take the lock before looking at shared data.

[Anders Johnsen, 2013-10-02 10:16:58]

PTAL

https://codereview.chromium.org/25631005/diff/1/runtime/bin/eventhandler_win.cc
File runtime/bin/eventhandler_win.cc (right):

https://codereview.chromium.org/25631005/diff/1/runtime/bin/eventhandler_win....
runtime/bin/eventhandler_win.cc:563: 
On 2013/10/02 08:49:22, Søren Gjesse wrote:
> Please add these static variables to the Windows EventHandlerImplementation
> class.

Done.

https://codereview.chromium.org/25631005/diff/1/runtime/bin/eventhandler_win....
runtime/bin/eventhandler_win.cc:637: // Double-checked locking, to avoid taking
the lock in most cases.
On 2013/10/02 08:49:22, Søren Gjesse wrote:
> You need to hold the lock before accessing shared variables. There is no
> guarantee that these reads are atomic (in almost all cases they are, but the
> compiler might fool us).

Done.

https://codereview.chromium.org/25631005/diff/1/runtime/bin/eventhandler_win....
runtime/bin/eventhandler_win.cc:1039:
EventHandlerImplementation::~EventHandlerImplementation() {
On 2013/10/02 08:49:22, Søren Gjesse wrote:
> Take the lock before looking at shared data.

Done.

[Søren Gjesse, 2013-10-02 10:49:43]

LGTM!