Move tests into a standalone package

[kevmoo]

At fe30f89 on mac
Also hitting this on travis: https://travis-ci.org/dart-lang/angular2/jobs/200125560#L750

As part of tool/run_codegen_tests.sh this is run: pub serve test --port 8283

Output

Loading source assets...
Transformer cycle detected:
  angular2 is transformed by angular2/transform/reflection_remover
  angular2 depends on angular_test
  angular_test is transformed by angular2/transform/codegen

[matanlurey]

FWIW I'm not sure this is solvable - there is no concept of dev_transformers - but that's basically what angular_test does. What I could do is remove the transformers from angular_test and edit the file in the presubmit to add them instead of checking in a presubmit

[kevmoo]

Do we just delete this code path then?

I'd love to have some tests that validate the transformers...

[matanlurey]

I don't think we have a resolution here @kevmoo - WDUT?

[matanlurey]

OK I have a solution.