Add a --reporter flag and expose the expanded reporter.

Add a --reporter flag and expose the expanded reporter.

Windows now uses the expanded reporter by default, since it doesn't
support using \r to go to the beginning of the line.

Closes #85

R=kevmoo@google.com

Committed: https://github.com/dart-lang/test/commit/543d9f3988ed96c6444ec30ff3d169b4d3ca89f9

[kevmoo, 2015-04-23 00:13:15]

LGTM modulo nits

https://codereview.chromium.org/1100873005/diff/1/lib/src/runner/reporter/exp...
File lib/src/runner/reporter/expanded.dart (right):

https://codereview.chromium.org/1100873005/diff/1/lib/src/runner/reporter/exp...
lib/src/runner/reporter/expanded.dart:83: ExpandedReporter(Iterable<Suite>
suites, {int concurrency, bool color: true})
TODO: document concurrency here

https://codereview.chromium.org/1100873005/diff/1/test/frontend/expect_async_...
File test/frontend/expect_async_test.dart (right):

https://codereview.chromium.org/1100873005/diff/1/test/frontend/expect_async_...
test/frontend/expect_async_test.dart:33: expect(callbackRun, isFalse);
sure? this failed for me.

https://codereview.chromium.org/1100873005/diff/1/test/frontend/expect_async_...
test/frontend/expect_async_test.dart:47: expect(callbackRun, isFalse);
ditto

[nweiz, 2015-04-23 00:15:39]

Code review changes

[nweiz, 2015-04-23 00:15:52]

https://codereview.chromium.org/1100873005/diff/1/lib/src/runner/reporter/exp...
File lib/src/runner/reporter/expanded.dart (right):

https://codereview.chromium.org/1100873005/diff/1/lib/src/runner/reporter/exp...
lib/src/runner/reporter/expanded.dart:83: ExpandedReporter(Iterable<Suite>
suites, {int concurrency, bool color: true})
On 2015/04/23 00:13:14, kevmoo wrote:
> TODO: document concurrency here

Done.

https://codereview.chromium.org/1100873005/diff/1/test/frontend/expect_async_...
File test/frontend/expect_async_test.dart (right):

https://codereview.chromium.org/1100873005/diff/1/test/frontend/expect_async_...
test/frontend/expect_async_test.dart:33: expect(callbackRun, isFalse);
On 2015/04/23 00:13:14, kevmoo wrote:
> sure? this failed for me.

Done.

https://codereview.chromium.org/1100873005/diff/1/test/frontend/expect_async_...
test/frontend/expect_async_test.dart:47: expect(callbackRun, isFalse);
On 2015/04/23 00:13:14, kevmoo wrote:
> ditto

Done.

[nweiz, 2015-04-23 00:16:06]

Committed patchset #2 (id:20001) manually as
543d9f3988ed96c6444ec30ff3d169b4d3ca89f9 (presubmit successful).