Dart: Merge message pipe query and read into one native call

Dart: Merge message pipe query and read into one native call

The native call uses a persistent message buffer per isolate.

This is a relanding of:

https://codereview.chromium.org/1405103002/ and
https://codereview.chromium.org/1410053002/

without using isolate data.

R=johnmccutchan@google.com

Committed: https://chromium.googlesource.com/external/mojo/+/321bf1a63aceaa4df0d478bbb56ad826f7aaca58

[zra, 2015-11-05 20:16:30]

Description was changed from

==========
Dart: Merge message pipe query and read into one native call

The native call uses a persistent message buffer per isolate.
==========

to

==========
Dart: Merge message pipe query and read into one native call

The native call uses a persistent message buffer per isolate.

This is a relanding of:

https://codereview.chromium.org/1405103002/ and
https://codereview.chromium.org/1410053002/

without using isolate data.
==========

[zra, 2015-11-05 20:18:10]

zra@google.com changed reviewers:
+ johnmccutchan@google.com

[Cutch, 2015-11-06 21:59:15]

LGTM with one suggestion and three requests

https://codereview.chromium.org/1415253008/diff/20001/mojo/public/dart/mojo/l...
File mojo/public/dart/mojo/lib/src/message_pipe.dart (right):

https://codereview.chromium.org/1415253008/diff/20001/mojo/public/dart/mojo/l...
mojo/public/dart/mojo/lib/src/message_pipe.dart:45: _status = new
MojoResult(_result[0]);
I wonder if we could just keep _data, etc in the _result list and just pass that
back and forth?

https://codereview.chromium.org/1415253008/diff/20001/mojo/public/dart/mojo/l...
mojo/public/dart/mojo/lib/src/message_pipe.dart:161: // are only valid until the
next call to this function by the same isolate.
Make this a doc comment.

https://codereview.chromium.org/1415253008/diff/20001/mojo/public/platform/da...
File mojo/public/platform/dart/mojo_natives.cc (right):

https://codereview.chromium.org/1415253008/diff/20001/mojo/public/platform/da...
mojo/public/platform/dart/mojo_natives.cc:753: data =
Dart_NewTypedData(Dart_TypedData_kByteData, blen);
Make this external to avoid a copy at every acquire.

https://codereview.chromium.org/1415253008/diff/20001/mojo/public/platform/da...
mojo/public/platform/dart/mojo_natives.cc:767: handles =
Dart_NewTypedData(Dart_TypedData_kUint32, hlen);
Make this external to avoid a copy at every acquire.

[zra, 2015-11-06 23:35:42]

https://codereview.chromium.org/1415253008/diff/20001/mojo/public/dart/mojo/l...
File mojo/public/dart/mojo/lib/src/message_pipe.dart (right):

https://codereview.chromium.org/1415253008/diff/20001/mojo/public/dart/mojo/l...
mojo/public/dart/mojo/lib/src/message_pipe.dart:45: _status = new
MojoResult(_result[0]);
On 2015/11/06 21:59:15, Cutch wrote:
> I wonder if we could just keep _data, etc in the _result list and just pass
that
> back and forth?

Done.

https://codereview.chromium.org/1415253008/diff/20001/mojo/public/dart/mojo/l...
mojo/public/dart/mojo/lib/src/message_pipe.dart:161: // are only valid until the
next call to this function by the same isolate.
On 2015/11/06 21:59:15, Cutch wrote:
> Make this a doc comment. 

Done.

https://codereview.chromium.org/1415253008/diff/20001/mojo/public/platform/da...
File mojo/public/platform/dart/mojo_natives.cc (right):

https://codereview.chromium.org/1415253008/diff/20001/mojo/public/platform/da...
mojo/public/platform/dart/mojo_natives.cc:753: data =
Dart_NewTypedData(Dart_TypedData_kByteData, blen);
On 2015/11/06 21:59:15, Cutch wrote:
> Make this external to avoid a copy at every acquire.

Done.

https://codereview.chromium.org/1415253008/diff/20001/mojo/public/platform/da...
mojo/public/platform/dart/mojo_natives.cc:767: handles =
Dart_NewTypedData(Dart_TypedData_kUint32, hlen);
On 2015/11/06 21:59:15, Cutch wrote:
> Make this external to avoid a copy at every acquire.

Done.

[zra, 2015-11-06 23:59:10]

Committed patchset #4 (id:60001) manually as
321bf1a63aceaa4df0d478bbb56ad826f7aaca58 (presubmit successful).