feat(compiler): support sync runtime compile

Adds new abstraction `Compiler` with methods
`compileComponentAsync` and `compileComponentSync`.
This is in preparation of deprecating `ComponentResolver`.

`compileComponentSync` is able to compile components
synchronously given all components either have an inline
template or they have been compiled before.

Also changes `TestComponentBuilder.createSync` to
take a `Type` and use the new `compileComponentSync` method.

Also supports overriding the component metadata even if
the component has already been compiled.

Also fixes #7084 in a better way.

BREAKING CHANGE:
`TestComponentBuilder.createSync` now takes a component type
and throws if not all templates are either inlined
are compiled before via `createAsync`.

Closes #9594

modules/@angular/core/src/linker.ts

@@ -7,6 +7,7 @@
  */
 
 // Public API for compiler
+export {Compiler} from './linker/compiler';
 export {ComponentFactory, ComponentRef} from './linker/component_factory';
 export {ComponentFactoryResolver, NoComponentFactoryError} from './linker/component_factory_resolver';
 export {ComponentResolver} from './linker/component_resolver';