This removes the magic from the `inject` test helper that would inspect
the current zone and would only work with our `async` test helper.
Now, `inject` is always synchronous, and if you are using a module
that requires async precompilation, you're required to call
`doAsyncPrecompilation` in your tests.
This is part of the breaking changes introduced with the swap
to each test having an AppModule.
Closes#9975Closes#9593
BREAKING CHANGE:
`TestInjector` is now renamed to `TestBed`
Before:
```js
import {TestInjector, getTestInjector} from '@angular/core/testing';
```
After:
```js
import {TestBed, getTestBed} from '@angular/core/testing';
```
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