fix(compiler-cli): do not add references to files outside of rootDir (#19770)

References to resources (such as .css files) that are generated into
the `outDir` directory outside of `rootDir` would cause a spurious
compiler error about not being able to find a files that ends in
'.ngstyle.ts'.

Also fixed a minor issue in compiler error reporting

Fixes: #19765, #19767

PR Close #19770

packages/compiler/src/aot/compiler.ts

@@ -113,7 +113,7 @@ export class AotCompiler {
       compMeta.template !.styleUrls.forEach((styleUrl) => {
         const normalizedUrl = this._host.resourceNameToFileName(styleUrl, file.fileName);
         if (!normalizedUrl) {
-          throw new Error(`Couldn't resolve resource ${styleUrl} relative to ${file.fileName}`);
+          throw syntaxError(`Couldn't resolve resource ${styleUrl} relative to ${file.fileName}`);
         }
         const needsShim = (compMeta.template !.encapsulation ||
                            this._config.defaultEncapsulation) === ViewEncapsulation.Emulated;