fix(ivy): ngcc generates setClassMetadata calls for ES5 bundles (#27438)

ngcc would feed ngtsc with the function declaration inside of an IIFE as
that is considered the class symbol's declaration node, according to
TypeScript's `ts.Symbol.valueDeclaration`. ngtsc however only considered
variable decls and actual class decls as potential class declarations,
so given the function declaration node it would fail to generate the
`setClassMetadata` call.

ngtsc no longer makes its own assumptions about what classes look like,
but always asks the reflection host to yield this kind of information.

PR Close #27438

packages/compiler-cli/src/ngcc/src/host/esm5_host.ts

@@ -38,7 +38,9 @@ export class Esm5ReflectionHost extends Esm2015ReflectionHost {
   /**
    * Check whether the given node actually represents a class.
    */
-  isClass(node: ts.Node): boolean { return super.isClass(node) || !!this.getClassSymbol(node); }
+  isClass(node: ts.Node): node is ts.NamedDeclaration {
+    return super.isClass(node) || !!this.getClassSymbol(node);
+  }
 
   /**
    * Find a symbol for a node that we think is a class.

packages/compiler-cli/src/ngtsc/annotations/src/metadata.ts

@@ -20,10 +20,7 @@ import {CtorParameter, Decorator, ReflectionHost} from '../../host';
  */
 export function generateSetClassMetadataCall(
     clazz: ts.Declaration, reflection: ReflectionHost, isCore: boolean): Statement|null {
-  // Classes come in two flavors, class declarations (ES2015) and variable declarations (ES5).
-  // Both must have a declared name to have metadata set on them.
-  if ((!ts.isClassDeclaration(clazz) && !ts.isVariableDeclaration(clazz)) ||
-      clazz.name === undefined || !ts.isIdentifier(clazz.name)) {
+  if (!reflection.isClass(clazz) || clazz.name === undefined || !ts.isIdentifier(clazz.name)) {
     return null;
   }
   const id = ts.updateIdentifier(clazz.name);

packages/compiler-cli/src/ngtsc/host/src/reflection.ts

@@ -423,7 +423,7 @@ export interface ReflectionHost {
   /**
    * Check whether the given node actually represents a class.
    */
-  isClass(node: ts.Node): boolean;
+  isClass(node: ts.Node): node is ts.NamedDeclaration;
 
   hasBaseClass(node: ts.Declaration): boolean;
 

packages/compiler-cli/src/ngtsc/metadata/src/reflector.ts

@@ -145,7 +145,7 @@ export class TypeScriptReflectionHost implements ReflectionHost {
     return map;
   }
 
-  isClass(node: ts.Node): boolean {
+  isClass(node: ts.Node): node is ts.NamedDeclaration {
     // In TypeScript code, classes are ts.ClassDeclarations.
     return ts.isClassDeclaration(node);
   }

packages/compiler-cli/src/ngtsc/metadata/src/resolver.ts

@@ -353,7 +353,7 @@ class StaticInterpreter {
       return this.visitExpression(node.expression, context);
     } else if (ts.isNonNullExpression(node)) {
       return this.visitExpression(node.expression, context);
-    } else if (isPossibleClassDeclaration(node) && this.host.isClass(node)) {
+    } else if (this.host.isClass(node)) {
       return this.visitDeclaration(node, context);
     } else {
       return DYNAMIC_VALUE;
@@ -565,7 +565,7 @@ class StaticInterpreter {
       return lhs[rhs];
     } else if (lhs instanceof Reference) {
       const ref = lhs.node;
-      if (isPossibleClassDeclaration(ref) && this.host.isClass(ref)) {
+      if (this.host.isClass(ref)) {
         let absoluteModuleName = context.absoluteModuleName;
         if (lhs instanceof NodeReference || lhs instanceof AbsoluteReference) {
           absoluteModuleName = lhs.moduleName || absoluteModuleName;
@@ -761,10 +761,6 @@ function identifierOfDeclaration(decl: ts.Declaration): ts.Identifier|undefined
   }
 }
 
-function isPossibleClassDeclaration(node: ts.Node): node is ts.Declaration {
-  return ts.isClassDeclaration(node) || ts.isVariableDeclaration(node);
-}
-
 function isVariableDeclarationDeclared(node: ts.VariableDeclaration): boolean {
   if (node.parent === undefined || !ts.isVariableDeclarationList(node.parent)) {
     return false;