Allowing `e` of any type in `void f(...) => e` in dart2js.

Allowing `e` of any type in `void f(...) => e` in dart2js.

Addresses https://github.com/dart-lang/sdk/issues/28941.

R=sigmund@google.com

Committed: https://github.com/dart-lang/sdk/commit/9928c5cb805dedf73b83ab051069e7a2e8cb0e06

[eernst, 2017-05-09 14:46:39]

eernst@google.com changed reviewers:
+ sigmund@google.com

[eernst, 2017-05-09 14:46:39]

Allowing `e` of any type in `void f(...) => e` in dart2js, as a step towards a
generalized void.

Addresses https://github.com/dart-lang/sdk/issues/28941.

[eernst, 2017-05-09 14:57:56]

Test cases are available in https://codereview.chromium.org/2870063002/:
tests/language/void_{block,arrow}_return_test.dart. I did not add them
to this CL in order to avoid git conflicts. Language tests run,
including those two from 2870063002.

[Siggi Cherem (dart-lang), 2017-05-09 17:19:34]

sigmund@google.com changed reviewers:
+ johnniwinther@google.com

[Siggi Cherem (dart-lang), 2017-05-09 17:19:34]

lgtm

ha, I can't believe we didn't used to have any tests covering this before. You
may want to copy this change to your other CL so you can land them atomically,
or add a .status file entry in the other CL that you can delete once this CL
lands.

[eernst, 2017-05-11 14:15:29]

Description was changed from

==========
Allowing `e` of any type in `void f(...) => e` in dart2js.

Addresses https://github.com/dart-lang/sdk/issues/28941.
==========

to

==========
Allowing `e` of any type in `void f(...) => e` in dart2js.

Addresses https://github.com/dart-lang/sdk/issues/28941.

R=sigmund@google.com

Committed:
https://github.com/dart-lang/sdk/commit/9928c5cb805dedf73b83ab051069e7a2e8cb0e06
==========

[eernst, 2017-05-11 14:15:31]

Committed patchset #4 (id:60001) manually as
9928c5cb805dedf73b83ab051069e7a2e8cb0e06 (presubmit successful).

[eernst, 2017-05-11 16:42:40]

I didn't actually copy the new test files into this CL. The reason
for not doing it is really bad: It all worked fine for dart2js also
after I landed the analyzer CL (2870363003), without status file
changes, but that's because test.py does not detect whether dart2js
has a static type warning or not.

So '//# 00: static type warning' is simply misleading for dart2js
in tests/language (but I suppose that's considered well-known by
everybody else than me ;-).

As it happens, compiler/dart2js/type_checker_test.dart started
failing when I landed this, and that's addressed in CL 2875983002.
That's a place where dart2js static warnings are actually tested.
As mentioned in that CL, we may need to make further adjustments
to type_checker_test in order to ensure good coverage of =>
functions, but that will be a new CL.