This is part of ongoing work to make core platform-independent.
BREAKING CHANGE
All private exports from 'angular2/src/core/facade/{lang,collection,exception_handler}' should be replaced with 'angular2/src/facade/{lang,collection,exception_handler}'.
The test injector now uses an XHR implementation based on DOM.getXHR,
which allows the current DOM adapter to dictate which XHR impl should
be used.
To prevent the changes to DOM adapter from introducing undesired new
dependencies into the benchmarks, separate the async facade into
a promise facade which is reexported by facade/async.
See #4539