fix(compiler): don’t type check property access of literal maps (#19301)

This was the behavior in Ng4, so we put the stricter
check behind the `fullTemplateTypeCheck` flag.
PR Close #19301

packages/compiler-cli/test/diagnostics/check_types_spec.ts

@@ -141,6 +141,12 @@ describe('ng type checker', () => {
           '<div>{{"hello" | aPipe}}</div>',
           `Argument of type '"hello"' is not assignable to parameter of type 'number'.`, '0:5');
     });
+    it('should report an index into a map expression', () => {
+      rejectOnlyWithFullTemplateTypeCheck(
+          '<div>{{ {a: 1}[name] }}</div>',
+          `Element implicitly has an 'any' type because type '{ a: number; }' has no index signature.`,
+          '0:5');
+    });
     it('should report an invalid property on an exportAs directive', () => {
       rejectOnlyWithFullTemplateTypeCheck(
           '<div aDir #aDir="aDir">{{aDir.fname}}</div>',