Add a changelog to barback.

Add a changelog to barback.

R=rnystrom@google.com
BUG=

Committed: https://code.google.com/p/dart/source/detail?r=33680

[Bob Nystrom, 2014-03-14 00:01:55]

lgtm

https://codereview.chromium.org/199133003/diff/1/pkg/barback/CHANGELOG.md
File pkg/barback/CHANGELOG.md (right):

https://codereview.chromium.org/199133003/diff/1/pkg/barback/CHANGELOG.md#new...
pkg/barback/CHANGELOG.md:10: * Transforms now pass their primary inputs through
to the next phase by default.
"Transforms" -> "Transformers"

[nweiz, 2014-03-14 00:06:52]

https://codereview.chromium.org/199133003/diff/1/pkg/barback/CHANGELOG.md
File pkg/barback/CHANGELOG.md (right):

https://codereview.chromium.org/199133003/diff/1/pkg/barback/CHANGELOG.md#new...
pkg/barback/CHANGELOG.md:10: * Transforms now pass their primary inputs through
to the next phase by default.
On 2014/03/14 00:01:55, Bob Nystrom wrote:
> "Transforms" -> "Transformers"

I thought we used "transformer" to refer to the class that knows how to
transform something and "transforms" to refer to the application of a
transformer to a specific primary input.

[Bob Nystrom, 2014-03-14 00:24:17]

https://codereview.chromium.org/199133003/diff/1/pkg/barback/CHANGELOG.md
File pkg/barback/CHANGELOG.md (right):

https://codereview.chromium.org/199133003/diff/1/pkg/barback/CHANGELOG.md#new...
pkg/barback/CHANGELOG.md:10: * Transforms now pass their primary inputs through
to the next phase by default.
On 2014/03/14 00:06:52, nweiz wrote:
> On 2014/03/14 00:01:55, Bob Nystrom wrote:
> > "Transforms" -> "Transformers"
> 
> I thought we used "transformer" to refer to the class that knows how to
> transform something and "transforms" to refer to the application of a
> transformer to a specific primary input.

SGTM.

[nweiz, 2014-03-14 00:56:20]

Committed patchset #1 manually as r33680 (presubmit successful).