Enable conditional directives by default.

Enable conditional directives by default.

R=brianwilkerson@google.com, iposva@google.com, sigmund@google.com

Committed: https://github.com/dart-lang/sdk/commit/bcd8ef3dea0caffa6a715191cc937fe48076dc81

[floitsch, 2016-04-01 09:46:04]

floitsch@google.com changed reviewers:
+ brianwilkerson@google.com, iposva@google.com, sigmund@google.com

[floitsch, 2016-04-01 09:46:05]

This is a silent launch of config imports.
This means:
- no Changelog entry (yet).
- no big announcements (yet).

We are confident that this version of config-imports is not going to change
anymore. By enabling it by default, we can start using it ourselves (outside of
toy examples).

[Siggi Cherem (dart-lang), 2016-04-01 16:36:44]

lgtm for dart2js - (I'm sure you are aware of Erik's changes for passing
options, just coordinate to minimize your merge conflicts)

[Ivan Posva, 2016-04-01 17:05:33]

VM parser change LGTM.
-Ivan

[vsm, 2016-04-01 17:17:29]

I don't see support here in the analyzer beyond parse and ignore.  We'll need it
in the element model to type check and to generate (DDC) code.  What's the plan
for that?

[floitsch, 2016-04-01 18:02:42]

On 2016/04/01 17:17:29, vsm wrote:
> I don't see support here in the analyzer beyond parse and ignore.  We'll need
it
> in the element model to type check and to generate (DDC) code.  What's the
plan
> for that?

Yes. compilers (and thus DDC) need to choose the correct target. That is, when
the analyzer frontend is used for anything else than analysis it needs to select
the right target. Thinking about it, this could potentially involve
transformers, too.

If the environment variables are correctly handled, it should be trivial to
implement.
I don't have any plans to implement it myself.

[Brian Wilkerson, 2016-04-01 22:59:38]

Other than as commented, lgtm.

https://codereview.chromium.org/1851753002/diff/1/pkg/analyzer/lib/src/genera...
File pkg/analyzer/lib/src/generated/engine.dart (left):

https://codereview.chromium.org/1851753002/diff/1/pkg/analyzer/lib/src/genera...
pkg/analyzer/lib/src/generated/engine.dart:1065: bool get
enableConditionalDirectives;
To avoid a breaking change, this should not be deleted but should be marked as
deprecated.

https://codereview.chromium.org/1851753002/diff/1/pkg/analyzer/lib/src/genera...
pkg/analyzer/lib/src/generated/engine.dart:1204: bool
enableConditionalDirectives = false;
This should be replaced by a deprecated getter that always returns `true`, and a
deprecated setter that does nothing.

[floitsch, 2016-04-13 14:50:00]

PTAL.
I changed it so that the tools still accept the flag (in accordance with the
silent launch).

https://codereview.chromium.org/1851753002/diff/1/pkg/analyzer/lib/src/genera...
File pkg/analyzer/lib/src/generated/engine.dart (left):

https://codereview.chromium.org/1851753002/diff/1/pkg/analyzer/lib/src/genera...
pkg/analyzer/lib/src/generated/engine.dart:1065: bool get
enableConditionalDirectives;
On 2016/04/01 22:59:38, Brian Wilkerson wrote:
> To avoid a breaking change, this should not be deleted but should be marked as
> deprecated.

Done.

https://codereview.chromium.org/1851753002/diff/1/pkg/analyzer/lib/src/genera...
pkg/analyzer/lib/src/generated/engine.dart:1204: bool
enableConditionalDirectives = false;
On 2016/04/01 22:59:38, Brian Wilkerson wrote:
> This should be replaced by a deprecated getter that always returns `true`, and
a
> deprecated setter that does nothing.

Done.

[Ivan Posva, 2016-04-13 15:23:52]

VM change still LGTM

-Ivan

[Siggi Cherem (dart-lang), 2016-04-13 16:03:28]

dart2js changes still lgtm

[floitsch, 2016-04-14 17:02:46]

Description was changed from

==========
Enable conditional directives by default.
==========

to

==========
Enable conditional directives by default.

R=brianwilkerson@google.com, iposva@google.com, sigmund@google.com

Committed:
https://github.com/dart-lang/sdk/commit/bcd8ef3dea0caffa6a715191cc937fe48076dc81
==========

[floitsch, 2016-04-14 17:02:48]

Committed patchset #4 (id:60001) manually as
bcd8ef3dea0caffa6a715191cc937fe48076dc81 (presubmit successful).