Remove MockData from the constructor parameters of MockTypescriptHost
since the entire Tour of Heroes (TOH) project is now loaded from disk.
Added a new method `reset()` to MockTypescriptHost that is necessary to
reset the state of the project before each spec if run to make sure
previous overrides are cleared.
PR Close#32752
```
NgLSHost: AngularLanguageServiceHost
NgLS: AngularLanguageService
```
NgLSHost should not depend on NgLS, because it introduces circular
dependency.
Instead, the `getTemplateAst` and `getTemplatAstAtPosition` methods should
be moved to NgLSHost and exposed as public methods.
This removes the circular dependency, and also removes the need for the
awkward 'setSite' method in NgLSHost.
PR Close#31122
Keen Yee Liau
Alan
Miško Hevery
Jason Aden