b803ecf7e7
Before #5375, injectAsync would check the return value and fail if it was not a promise, to help users remember that they need to return a promise from an async test. #5375 removed that with the introduction of the testing zone. This un-deprecates `injectAsync` until we can resolve https://github.com/angular/angular/issues/5515. To be clear, this means that `inject` and `injectAsync` are now identical except that `injectAsync` will fail if the test does not return a promise, and `inject` will fail if the test returns any value. Closes #5721