dart2js: Smaller async error sequence when only one handler

dart2js: Smaller async error sequence when only one handler

R=floitsch@google.com

Committed: https://github.com/dart-lang/sdk/commit/aab31aa1a4ef4afc772e93fc07f61ac10b81244e

[sra1, 2017-05-04 04:04:13]

Patchset #1 (id:1) has been deleted

[sra1, 2017-05-04 04:06:11]

sra@google.com changed reviewers:
+ floitsch@google.com

[sra1, 2017-05-04 04:06:12]

WDYT? Seems to benefit about 75% of async methods in a certain large app.

[floitsch, 2017-05-04 08:52:05]

LGTM.

https://codereview.chromium.org/2856223004/diff/20001/pkg/compiler/lib/src/js...
File pkg/compiler/lib/src/js/rewrite_async.dart (right):

https://codereview.chromium.org/2856223004/diff/20001/pkg/compiler/lib/src/js...
pkg/compiler/lib/src/js/rewrite_async.dart:1922: hasHandlerLabels = true;
This is too confusing, but I'm guessing this is just temporary.

Would you make a virtual function for the actual statement?

https://codereview.chromium.org/2856223004/diff/20001/pkg/compiler/lib/src/js...
pkg/compiler/lib/src/js/rewrite_async.dart:2107: hasHandlerLabels = true;
ditto.

[sra1, 2017-05-05 21:48:14]

Patchset #2 (id:40001) has been deleted

[sra1, 2017-05-05 21:52:34]

https://codereview.chromium.org/2856223004/diff/20001/pkg/compiler/lib/src/js...
File pkg/compiler/lib/src/js/rewrite_async.dart (right):

https://codereview.chromium.org/2856223004/diff/20001/pkg/compiler/lib/src/js...
pkg/compiler/lib/src/js/rewrite_async.dart:1922: hasHandlerLabels = true;
On 2017/05/04 08:52:05, floitsch wrote:
> This is too confusing, but I'm guessing this is just temporary.

I added a field comment and a TODO comment here to help with that

> 
> Would you make a virtual function for the actual statement?

The statement could be different at this point and in the no-handler case. It
takes different variables as inputs.

[sra1, 2017-05-09 21:44:57]

Description was changed from

==========
dart2js: Smaller async error sequence when only one handler
==========

to

==========
dart2js: Smaller async error sequence when only one handler

R=floitsch@google.com

Committed:
https://github.com/dart-lang/sdk/commit/aab31aa1a4ef4afc772e93fc07f61ac10b81244e
==========

[sra1, 2017-05-09 21:44:59]

Committed patchset #3 (id:80001) manually as
aab31aa1a4ef4afc772e93fc07f61ac10b81244e (presubmit successful).