fix(ivy): support multiple directives with the same selector (#27298)

Previously the concept of multiple directives with the same selector was
not supported by ngtsc. This is due to the treatment of directives for a
component as a Map from selector to the directive, which is an erroneous
representation.

Now the directives for a component are stored as an array which supports
multiple directives with the same selector.

Testing strategy: a new ngtsc_spec test asserts that multiple directives
with the same selector are matched on an element.

PR Close #27298

packages/compiler/src/compiler_facade_interface.ts

@@ -128,7 +128,7 @@ export interface R3ComponentMetadataFacade extends R3DirectiveMetadataFacade {
   animations: any[]|undefined;
   viewQueries: R3QueryMetadataFacade[];
   pipes: Map<string, any>;
-  directives: Map<string, any>;
+  directives: {selector: string, expression: any}[];
   styles: string[];
   encapsulation: ViewEncapsulation;
   viewProviders: Provider[]|null;