StaticInjectionError for service after migrating to Angular 5. // Solution: `--preserve-symlinks`

Type of Issue

Service package error after migrate to Angular 5

[x] Bug Report [ ] Feature Request

## Description

I have an Angular CLI generated project that just has only one service file my-test.service.ts

@Injectable()
export class MyTestService {
   ......
}

I publish it to NPM using ng-packagr. I can use the package in my other projects before migrating to Angular 5. After migration, I got error:
 
ERROR Error: StaticInjectorError[MyTestService]: 
  StaticInjectorError[MyTestService]: 
    NullInjectorError: No provider for MyTestService!
    at _NullInjector.get (core.js:923)
    at resolveToken (core.js:1211)
    at tryResolveToken (core.js:1153)
    at StaticInjector.get (core.js:1024)
    at resolveToken (core.js:1211)
    at tryResolveToken (core.js:1153)
    at StaticInjector.get (core.js:1024)
    at resolveNgModuleDep (core.js:10585)
    at NgModuleRef_.get (core.js:11806)
    at resolveDep (core.js:12302)

#### How To Reproduce



#### Expected Behaviour



#### Version Information

ng-packagr: v1.6.0 node: v8.x.y @angular: v5.0.0 rxjs: zone.js:

_please include any version information that might be relevant, e.g. other third-party libraries_

[trollkotze]

Why is this closed? It seems it is not fixed, or is it? I see neither a fix nor a clear explanation.

[kolbma]

@dherges should this really be closed?