Devoncarew add analyzer tests

This CL adds analyzer integration level tests:

- add high level tests of the analyzer service, so that we know when the analyzer integration regresses
- fix an issue w/ the outline tests, when the tests are run more then once
- rev the dart2js dependency, and fix an issue w/ the new dart2js version
- analyzer tests disabled when compiled to javascript :(
- tried to make the `git.pack parsePack` test more reliable

@umop