Do some housekeeping in tools/testing/dart

Do some housekeeping in tools/testing/dart

- Fix dartanalyzer warnings about unused variables and missing returns
- Remove trailing whitespace
- Add a dummy pubspec.yaml so editors recognize it as a Dart project

R=whesse@google.com

Committed: https://github.com/dart-lang/sdk/commit/902d9ee7e8543f1298b62a64c4007e49ca85d32e

[asgerf, 2017-01-17 13:18:43]

Description was changed from

==========
Do some housekeeping in tools/testing/dart

- Fix dartanalyzer warnings about unused variables and missing returns
- Remove trailing whitespace
- Adds a dummy pubspec.yaml so editors recognize it as a Dart project
==========

to

==========
Do some housekeeping in tools/testing/dart

- Fix dartanalyzer warnings about unused variables and missing returns
- Remove trailing whitespace
- Add a dummy pubspec.yaml so editors recognize it as a Dart project
==========

[asgerf, 2017-01-17 13:27:21]

asgerf@google.com changed reviewers:
+ whesse@google.com

[Bill Hesse, 2017-01-17 14:38:08]

LGTM.

https://codereview.chromium.org/2633213003/diff/1/tools/testing/dart/test_opt...
File tools/testing/dart/test_options.dart (right):

https://codereview.chromium.org/2633213003/diff/1/tools/testing/dart/test_opt...
tools/testing/dart/test_options.dart:1018: return null;
I would add a comment "unreachable" here.

[asgerf, 2017-01-17 14:40:07]

https://codereview.chromium.org/2633213003/diff/1/tools/testing/dart/test_opt...
File tools/testing/dart/test_options.dart (right):

https://codereview.chromium.org/2633213003/diff/1/tools/testing/dart/test_opt...
tools/testing/dart/test_options.dart:1018: return null;
On 2017/01/17 14:38:08, Bill Hesse wrote:
> I would add a comment "unreachable" here.

Done.

[asgerf, 2017-01-17 15:02:51]

Description was changed from

==========
Do some housekeeping in tools/testing/dart

- Fix dartanalyzer warnings about unused variables and missing returns
- Remove trailing whitespace
- Add a dummy pubspec.yaml so editors recognize it as a Dart project
==========

to

==========
Do some housekeeping in tools/testing/dart

- Fix dartanalyzer warnings about unused variables and missing returns
- Remove trailing whitespace
- Add a dummy pubspec.yaml so editors recognize it as a Dart project

R=whesse@google.com

Committed:
https://github.com/dart-lang/sdk/commit/902d9ee7e8543f1298b62a64c4007e49ca85d32e
==========

[asgerf, 2017-01-17 15:02:53]

Committed patchset #2 (id:20001) manually as
902d9ee7e8543f1298b62a64c4007e49ca85d32e (presubmit successful).