Fast path Dart Timeline events with no arguments to avoid calling JSON.encode

Fast path Dart Timeline events with no arguments to avoid calling JSON.encode

BUG=
R=zra@google.com

Committed: https://github.com/dart-lang/sdk/commit/5725b0a0a0cb9e44985f813cd2e17e4e71d29c33

[Cutch, 2015-11-13 00:35:07]

Description was changed from

==========
Fast path Dart Timeline events with no arguments to avoid calling JSON.encode

BUG=
==========

to

==========
Fast path Dart Timeline events with no arguments to avoid calling JSON.encode

BUG=
==========

[Cutch, 2015-11-13 00:35:07]

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

[zra, 2015-11-13 02:54:01]

https://codereview.chromium.org/1441683005/diff/1/sdk/lib/developer/timeline....
File sdk/lib/developer/timeline.dart (right):

https://codereview.chromium.org/1441683005/diff/1/sdk/lib/developer/timeline....
sdk/lib/developer/timeline.dart:47: Map instantArguments = {};
Since _argumentsAsJson does the right thing with null, I think you only need to
initialize this in the (arguments is Map) case.

https://codereview.chromium.org/1441683005/diff/1/sdk/lib/developer/timeline....
sdk/lib/developer/timeline.dart:121: Map instantArguments = {};
ditto

[Cutch, 2015-11-13 15:38:39]

https://codereview.chromium.org/1441683005/diff/1/sdk/lib/developer/timeline....
File sdk/lib/developer/timeline.dart (right):

https://codereview.chromium.org/1441683005/diff/1/sdk/lib/developer/timeline....
sdk/lib/developer/timeline.dart:47: Map instantArguments = {};
On 2015/11/13 02:54:01, zra wrote:
> Since _argumentsAsJson does the right thing with null, I think you only need
to
> initialize this in the (arguments is Map) case.

Done.

https://codereview.chromium.org/1441683005/diff/1/sdk/lib/developer/timeline....
sdk/lib/developer/timeline.dart:121: Map instantArguments = {};
On 2015/11/13 02:54:01, zra wrote:
> ditto

Done.

[zra, 2015-11-13 15:40:29]

lgtm

[Cutch, 2015-11-13 15:47:27]

Committed patchset #4 (id:60001) manually as
5725b0a0a0cb9e44985f813cd2e17e4e71d29c33 (presubmit successful).