Add a sleep function to dart:io

Add a sleep function to dart:io

The sleep function is a top-level function.

R=ager@google.com

BUG=https://code.google.com/p/dart/issues/detail?id=9254

Committed: https://code.google.com/p/dart/source/detail?r=20952

[Søren Gjesse, 2013-04-04 16:21:52]

As you can see I added an all static OS class to runtime/platform. As the
runtime/vm subdirectory already have one I had to use a different namespace.
Also the file names had to be different to please GYP.

We could look into moving most of the static functions from OS in runtime/vm to
OS in runtime/platform going or we could skip having the OS class in
runtime/platform and for now just place the OS sleep implementation in
runtime/bin/platform_xxx.cc.

[Mads Ager (google), 2013-04-05 05:51:48]

The code looks good to me. I think I would skip adding this to platform at this
point since this is not shared anyway and therefore requires the namespace
hacking. Let's just add it in the runtime/bin directory for now?

https://codereview.chromium.org/13641005/diff/1/sdk/lib/io/process.dart
File sdk/lib/io/process.dart (right):

https://codereview.chromium.org/13641005/diff/1/sdk/lib/io/process.dart#newcode7
sdk/lib/io/process.dart:7: // TODO(ager): The only reason for this class is that
we
I *think* this has been fixed now. As a followup we should see if we can get rid
of the classes around some of these externals.

[Søren Gjesse, 2013-04-05 09:33:22]

Moved the OS specific code to runtime/bin/utils_xxx.

https://codereview.chromium.org/13641005/diff/1/sdk/lib/io/process.dart
File sdk/lib/io/process.dart (right):

https://codereview.chromium.org/13641005/diff/1/sdk/lib/io/process.dart#newcode7
sdk/lib/io/process.dart:7: // TODO(ager): The only reason for this class is that
we
On 2013/04/05 05:51:48, Mads Ager wrote:
> I *think* this has been fixed now. As a followup we should see if we can get
rid
> of the classes around some of these externals.

No, it is still not fixed.

[Søren Gjesse, 2013-04-05 09:35:57]

Committed patchset #3 manually as r20952 (presubmit successful).