Drop support for older Barback versions.

Drop support for older Barback versions.

This also allows us to limit our tests to the latest barback, which
simplifies the necessary infrastructure and speeds up the tests
dramatically.

Closes #1367

R=rnystrom@google.com

Committed: https://github.com/dart-lang/pub/commit/a1dd3484795b2bc221aaa8d007f3162251b3c08e

[nweiz, 2015-12-16 21:29:15]

nweiz@google.com changed reviewers:
+ rnystrom@google.com

[nweiz, 2015-12-16 21:29:15]

I'm planning to land this eagerly, since it's becoming pretty clear that the
pain of maintaining this is higher than any benefit. If Martin's data comes back
showing that it's crucial to keep supporting older barbacks, we can revert, but
I doubt that will happen.

[Bob Nystrom, 2015-12-16 23:39:10]

LGTM. The tests must run much faster now!

Before you land this, I'd like you to check with Dan and/or Kevin and make sure
they're OK with it too since it touches on SDK compatibility.

[nweiz, 2015-12-17 19:45:38]

Description was changed from

==========
Drop support for older Barback versions.

This also allows us to limit our tests to the latest barback, which
simplifies the necessary infrastructure and speeds up the tests
dramatically.
==========

to

==========
Drop support for older Barback versions.

This also allows us to limit our tests to the latest barback, which
simplifies the necessary infrastructure and speeds up the tests
dramatically.

Closes #1367
==========

[nweiz, 2015-12-17 22:11:33]

On 2015/12/16 23:39:10, Bob Nystrom wrote:
> LGTM. The tests must run much faster now!
> 
> Before you land this, I'd like you to check with Dan and/or Kevin and make
sure
> they're OK with it too since it touches on SDK compatibility.

Dan and Kevin are on board.

[nweiz, 2015-12-17 23:20:21]

Description was changed from

==========
Drop support for older Barback versions.

This also allows us to limit our tests to the latest barback, which
simplifies the necessary infrastructure and speeds up the tests
dramatically.

Closes #1367
==========

to

==========
Drop support for older Barback versions.

This also allows us to limit our tests to the latest barback, which
simplifies the necessary infrastructure and speeds up the tests
dramatically.

Closes #1367

R=rnystrom@google.com

Committed:
https://github.com/dart-lang/pub/commit/a1dd3484795b2bc221aaa8d007f3162251b3c08e
==========

[nweiz, 2015-12-17 23:20:23]

Committed patchset #1 (id:1) manually as
a1dd3484795b2bc221aaa8d007f3162251b3c08e (presubmit successful).