fix #29228, let* precedence should match generated expression

fix #29228, let* precedence should match generated expression

R=vsm@google.com

Committed: https://github.com/dart-lang/sdk/commit/247fc68d21fc099de51fd26b1509958d9f2154c8

[Jennifer Messerly, 2017-04-05 19:34:32]

jmesserly@google.com changed reviewers:
+ vsm@google.com

[Jennifer Messerly, 2017-04-05 19:34:33]

FYI, I did regenerate the SDK but it refuses to upload those files.

[Jennifer Messerly, 2017-04-05 19:35:51]

On 2017/04/05 19:34:33, Jennifer Messerly wrote:
> FYI, I did regenerate the SDK but it refuses to upload those files.

Here's an example of improvements in the SDK, though:
-        _internal.Sort.sort(E)(this, (compare != null ? compare :
collection.ListMixin._compareAny));
+        _internal.Sort.sort(E)(this, compare != null ? compare :
collection.ListMixin._compareAny);

-          this.cookies[dartx.add](((() => {
+          this.cookies[dartx.add]((() => {
             cookie.httpOnly = true;
             cookie.path = "/";
             return cookie;
-          })()));
+          })());


... so in a bunch of cases this actually reduces parens.

[vsm, 2017-04-05 19:37:17]

nice!

lgtm

[Jennifer Messerly, 2017-04-05 19:40:51]

Description was changed from

==========
fix #29228, let* precedence should match generated expression
==========

to

==========
fix #29228, let* precedence should match generated expression

R=vsm@google.com

Committed:
https://github.com/dart-lang/sdk/commit/247fc68d21fc099de51fd26b1509958d9f2154c8
==========

[Jennifer Messerly, 2017-04-05 19:40:52]

Committed patchset #2 (id:10001) manually as
247fc68d21fc099de51fd26b1509958d9f2154c8 (presubmit successful).