[corelib] dart:developer timeline flow events

[corelib] dart:developer timeline flow events

This change adds an API to dart:developer Timeline for
adding flow events to the timeline. For details see the
changes in:

sdk/lib/developer/timeline.dart

R=rmacnak@google.com

Committed: https://github.com/dart-lang/sdk/commit/633ed4cf83792c27ac8a5424e9117aaa3a6dfcf2

[zra, 2017-07-28 20:01:59]

Description was changed from

==========
dart:developer timeline flow events
==========

to

==========
[corelib] dart:developer timeline flow events

This change adds an API to dart:developer Timeline for
adding flow events to the timeline. For details see the
changes in:

sdk/lib/developer/timeline.dart
==========

[zra, 2017-07-28 20:02:15]

zra@google.com changed reviewers:
+ konkers@google.com, rmacnak@google.com

[rmacnak, 2017-07-28 20:27:54]

cc Chinmay. It might be nice to extend the flow event for a frame so it is
connected to the paint phase in the framework.

https://codereview.chromium.org/2985253002/diff/60001/sdk/lib/developer/timel...
File sdk/lib/developer/timeline.dart (right):

https://codereview.chromium.org/2985253002/diff/60001/sdk/lib/developer/timel...
sdk/lib/developer/timeline.dart:56: return new Flow._(_begin, id = id ??
_getNextAsyncId());
Just `id ?? _getNextAsyncId()`. Don't need to write back to the parameter.

https://codereview.chromium.org/2985253002/diff/60001/sdk/lib/developer/timel...
sdk/lib/developer/timeline.dart:326: _argumentsAsJson(_arguments));
The arguments are already in the duration event, so I don't think they need to
be repeated in the flow event.

[zra, 2017-07-28 21:31:50]

https://codereview.chromium.org/2985253002/diff/60001/sdk/lib/developer/timel...
File sdk/lib/developer/timeline.dart (right):

https://codereview.chromium.org/2985253002/diff/60001/sdk/lib/developer/timel...
sdk/lib/developer/timeline.dart:56: return new Flow._(_begin, id = id ??
_getNextAsyncId());
On 2017/07/28 20:27:54, rmacnak wrote:
> Just `id ?? _getNextAsyncId()`. Don't need to write back to the parameter.

Done.

https://codereview.chromium.org/2985253002/diff/60001/sdk/lib/developer/timel...
sdk/lib/developer/timeline.dart:326: _argumentsAsJson(_arguments));
On 2017/07/28 20:27:54, rmacnak wrote:
> The arguments are already in the duration event, so I don't think they need to
> be repeated in the flow event.

According to tests, it looks like I need to maintain the invariant that events
from an isolate have at least one argument containing the isolate id. Passing
null here instead of _arguments does that.

[rmacnak, 2017-07-28 22:24:39]

lgtm

[zra, 2017-07-31 14:46:56]

Description was changed from

==========
[corelib] dart:developer timeline flow events

This change adds an API to dart:developer Timeline for
adding flow events to the timeline. For details see the
changes in:

sdk/lib/developer/timeline.dart
==========

to

==========
[corelib] dart:developer timeline flow events

This change adds an API to dart:developer Timeline for
adding flow events to the timeline. For details see the
changes in:

sdk/lib/developer/timeline.dart

R=rmacnak@google.com

Committed:
https://github.com/dart-lang/sdk/commit/633ed4cf83792c27ac8a5424e9117aaa3a6dfcf2
==========

[zra, 2017-07-31 14:46:58]

Committed patchset #6 (id:100001) manually as
633ed4cf83792c27ac8a5424e9117aaa3a6dfcf2 (presubmit successful).

[Chinmay, 2017-08-01 00:11:23]

On 2017/07/28 at 20:27:54, rmacnak wrote:
> cc Chinmay. It might be nice to extend the flow event for a frame so it is
connected to the paint phase in the framework.

We already trace the entire flow from the time beginFrame is called (which
include the layout and paint) to the point after the SwapBuffers call in the
engine.